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85_Ciera_Rebuild
01-05-2008, 06:05 AM
I wanted to start a thread here on Tuddi's Vehicle...RE.. (http://www.a-body.net/forums/showthread.php?p=3894#post3894)

1. Based upon this picture showing inside view of distributor (http://upload.hraunfjord.org/files/DistInside.jpg), it most likely represents (in US) an "Electronic Module Retard (EMR) Ignition System," that was used on 1980-81 GM Passenger Cars.

If yours has a 5 spade-module....then this may be the correct distributor (EMR)...I have no idea if this distributor came with this vehicle...but something stinks if you have a later model-year vehicle (what is model year?).

I am looking at a Mitchell's Electronic Ignition manual, which covers 1972-1985 model years. But, this shows several ways in which it could have been hooked up.

On this module, the module's spades on one side are labeled R-L-H in this manual, but yours are labeled H-L-D (best I can see).

Question - Does your module's spade-H wire go to a vacuum switch? On this diagram I have, the wire on the outer spade (on three spade connector side) goes to this vacuum switch.

The function of this vacuum switch is to retard timing about 10 degrees.

I noticed this distributor also has a vacuum advance on it? If so, what is it hooked up to, and is it working?

Tuddi
01-05-2008, 06:45 AM
Thanks for taking the time to look into this.

The car is from 1985, and has suffered unimaginable neglect and sparepart abuse and emergency fixes that became longtime "solutions".

The original composition of the vehicle is a big mystery to me. It has a carb, electrical gaspump (aftermarket one that's sitting on the inner fender under the hood). I did buy a new mechanical gaspump, but after attaching it to the car, I discovered that there was no cam or anything on the other side of the mounting hole to jerk the pump. So the car was born with an electric pump, and without possibility of putting a mechanical one. Regardless of that fact, there are 2 lines leading from the gastank. One for the fuel, and the other one for returning overpressure... which one would find on FI engines and mechanical gaspumps. So was the car FI from the start? Dunno. Maybe it was just normal to send the cars on the market with both fuel lines, regardless of model of engine? I find that hard to believe.

The distributor seems to be foreign to the car... at least the ICM is not supposed to be on this kind of engine.... only dicovered earlier tonight after mickstan_VR aired the possibility of it not belonging there (http://www.a-body.net/forums/showpost.php?p=3874&postcount=35).

The idling is erratic, but to live with. However, the gas consumption is very high as we have discussed elsewhere, and it can of course be explained with an ignition system that belongs to some totally different engine.

Yes, the vacuum advance is there. Does it work?... I honestly don't know. Some months ago I sucked on the vacuum hose leading to it while the engine was idle, and there was no audible change in the engine at all. I gassed it up and sucked away... and nothing changed either.

Tomorrow I will open the distributor again, suck on it and try to visually confirm if it moves or not. It wouldn't surprise me if it is not connected to anything at all.

RLH (http://www.a-body.net/forums/showpost.php?p=3880&postcount=36) vs HLD (http://www.a-body.net/forums/showpost.php?p=3884&postcount=37)

Maybe it's just the computer that's bad... but where it is to be found in the car beats the crap out of me. I have been under the dashboard several times, also removed the dash a couple of times... and seen nothing that resembles a puter box. Not even the plug where one supposedly checks the codes is to be found in the car.... BUT... I have had the "check engine" light to come on a few times, and after minutes... or days... it goes off by itself again. So there must be a puter hiding somewhere.

Maybe the greatest mistery is that the car still drives after all the bad worksmanship that's gone into it over the years?

I will also try and trace the "H" wire back to whatever it connects to (if it connects to anything at all).

Again, many thanks for looking into this!

a1veedubber
01-05-2008, 01:34 PM
I don't have a whole lot to add except that:

1) Having the two fuel lines to the tank is correct, it was an emissions control thing back then. The fuel vapor cannister that this was hooked to originally would have sat on the passenger side inner fender, in the same location as the battery sits on the drivers side. It is a black cylindrical plastic thing.

2)The fuel pump would have originally been in the tank, not sure if it died & the other was a replacement or if it was added to assist in getting fuel?? My VW gas both an in-tank AND inline pump from the factory

3)Your computer would have originally been right behind your glovebox. If the SES light comes on I would think it must still be there somewhere!

85_Ciera_Rebuild
01-05-2008, 06:56 PM
The original composition of the vehicle is a big mystery to me.


I don't read every thread in this forum....I was not aware of this other thread.

I'll have to read thru this other thread to see what has been said...before I say more here.

But, I wanted to go thru this distributor to make sure it is setup correctly....and then move onto another topic....but, the problem here is that this distributor's timing curve may not match this engine. And getting OEM timing specs may not be possible.

If this Vaccum Advance and Retarding mechanisms are not working properly, then it needs to be fixed first....especially, Vacuum Advance.

I would bet your vehicle has no power...its a flat response.

Let me read that other thread first...

LordDurock
01-05-2008, 07:13 PM
yea reading we need to confer we have the right dis.
you said you got the right carb for it awhile back? if thats the case did you rebuild it and trun it with a vac gauge (i geuss you did both)

how do you plugs look as well as the wires and dis cap.

does this go away when you get into the gas?

okay im going to stop asking qeustions. and i say i love diesel.

Tuddi
01-05-2008, 10:11 PM
Actually the engine responds extremely well, and doesn't have any lack of power issue. Going from 0-100 kmph (60 mph) on a straight stretch of road with spare tire, full tank of gas, tools in the trunk and my own weight, lands somewhere around the 11 seconds mark, which is very good for this old a car. I think these tested around 10 seconds when new, so I have no complaints in that department.

I opened up the distributor and sucked on the vacuum advance... it leaked air and didn't pull it's lever which is connected. Naturally I disconnected it and rechecked the vacuum lines. I am absolutely 100% sure this time that there are no leaks at all. The airmix screw on the carb got a rubber gasket up by it's head, so it doesn't rattle at all, and should not give any erratic false air (if it ever did that).

The engine is still not running smoothly...

Puter behind the glovebox... that might be the place for it to hide... not been with my hands or head up there for anything but to hang up hanging speaker wires.

LordDurock.
I changed the sparkplugs yesterday, and it didn't improve the idle. The ignition wires are Mopar and have less than 2000 miles on them, so I don't have any reason to suspect that to be the cause of my problems. The distribution cap is clean and the connectors are dirt free (used to have a thick layer of white alu oxidated material when I got the car) and the distributor hammer is also clean.

This irregularity that is audible when the engine runs idle, is not felt or heard at all when driving around. So it is a problem I can live with... even though I don't like it.

The carb was rebuilt for me... but by people who couldn't even put all the screws in it before they wanted to install it in the car... so no, I am sure there was no vacuum checking done before it was installed. I have had it to 2 different tune-up places, and neither one managed to fine tune the engine, but in both cases the carb was taken apart, cleaned and put together again.

85_Ciera_Rebuild
01-05-2008, 10:46 PM
...car is from 1985...

I looked again in Mitchell Manual, there was another application that had a 5-Spade Module, which worked differently....and was designed for a 2.8 L Motor (Vin R) used on 1981-1986 GMC light pickup trucks, which had a carburetor.

Two different systems:

1. Electronic Module Retard (EMR) Ignition System

2. High Energy Ignition (HEI): Electronic Spark Control (ESC)

This second system (ESC) had a detonation sensor on the motor; on mine (2.8 Vin W), it is located on back-side of motor (fire-wall side)...yours maybe located somewhere else.

&&&&&&&&&&&&&&&&&&&&&&&&

Now, I'm going to talk about your post over here (http://www.a-body.net/forums/showpost.php?p=3869&postcount=34)

Q - What sensor is marked #1

A - I can not see the wires, could it be a detonation sensor? Again, mine is located on back-side of motor...but they could have put it there. Are there two wires only, and where do the wires go? Do they go to a box...that other wires from the distributor go to also?

If you have an ESC system, it looks like from this schematic, that all the wires from the 3-Spade hookup (module), and detonation sensor's 2-wires go to a box.

If this sensor is a detonation sensor, it will not work at idle (have no effect when you disconnect it).

&&&&&&&&&&

Q - "check engine" light

Does it say "check engine" or something else?

I'm not sure your vehicle had a computer in this vehicle....there could have been a small box for the ESC distributor system...and nothing more.

Does this vehicle have a sticker in engine compartment with "Vin R" on it?

Does this vehicle have a long vehicle identification number, with the letter R in it? If so, at what digit position, from left to right, is it?

85_Ciera_Rebuild
01-05-2008, 10:50 PM
I opened up the distributor and sucked on the vacuum advance... it leaked air and didn't pull it's lever which is connected.


Can you manually move the lever from inside (move the "breaker plate")???

We need to find out first which engine you have...as asked before...is it Vin R?

Since I assume this vehicle was designed for overseas marketplace, GM may have cut costs..and never put a computer in it.

Tuddi
01-05-2008, 11:55 PM
Yes, the vacuum advance lever could be moved manually.

I don't know if there is any way possible of tracing back info on the car through it's serial number... if someone here knows a way, then the number is as follows: PRU1W19XFS108380

As far as I am informed (badly informed maybe) it should be the 8th number in the serial number that determins which series the car is, and my bluesmobile would in that case be "vin X", and the car was manufactured in Mexico.

No, there is no "vin" sticker under the hood, in the doors or elsewhere. It's been given a paintjob a couple of times as it looks, and there have been made no efforts to protect stickers and such at all.

The light in the dash displayed "Check Engine".

It hasn't lit up again in the past 3 or 4 months though.

I did not have the time (or manage to gear up the right attitude) to trace the "H" wire anywhere... the wiring is not so easy to access after I arranged the initial massive wire mess under the hood, which contained several wires connected to thin air. Now everything is taped up in a flexible tube. Not something I peel up and close again in minutes.

Interesting find you did there with the 1981-1986 GMC light pickup trucks using the EMR system. The engine could very well have been swapped somewhere in the past to a similar engine that would fit in with minimal effort.

You have probably hit the nail on the head!

Tuddi
01-06-2008, 12:00 AM
Ps.
Not thought about this before... but why would the dashboard lights display text in ENGLISH, when the car was produced for central and south american markets in spanish speaking Mexico? Maybe it was only available in one language, one design from one producer? But it would make sense having the dash in Spanish since less than 5% of the populations in SA understand English?

LordDurock
01-06-2008, 12:41 AM
the computer should be a shine metal box..................

85_Ciera_Rebuild
01-06-2008, 01:31 AM
vacuum advance lever could be moved

1. PRU1W19XFS108380

2. The light in the dash displayed "Check Engine".

Interesting find you did there with the 1981-1986 GMC light pickup trucks using the
ESRsystem.

1. "In North America, GM uses universal three-character alphanumeric RPO codes to refer to a specific car option, including engine model.
...
...
GM LAAM (Latin America, Africa and Mid-East) and GM Europe uses four- to six-character SKU codes, such as CN22E, to represent family, displacement and engine features (http://en.wikipedia.org/wiki/List_of_GM_engines)."

2. Big Question Mark Here - Since this engine has no EGR, CAT, O2, etc, then if a computer still exists in vehicle, it is doing nothing (most likely). Somebody on this forum ought to know where they stuffed it, anybody?

Is there an ALDL Plug (http://www.techedge.com.au/vehicle/aldl8192/8192hw.htm) under driver's side dash? Scroll down page.

3. High Energy Ignition (HEI): Electronic Spark Control (ESC) for 1981-1986 GMC light pickup trucks

85_Ciera_Rebuild
01-06-2008, 01:49 AM
the vacuum advance lever


I only checked to see if this vehicle,

1984 GMC S15 JIMMY V6 2.8 Liter 2BBL

had a Vacuum Advance...and yes it did...there is a difference between Automatic and Manual transmissions for this product, so you have to let them know its for the automatic transmission.

Is there a picture of the carburetor that shows vacuum ports...smaller ones? How many?

One of them (vacuum port) should be going from the carburetor to the distributor....at idle, there should be no vacuum in this hose to carburetor.

Tuddi
01-06-2008, 03:23 AM
The ALDL plug is what I have tried to find under the dash, around the steering column. I have had the whole dash removed from there and had clear view at all the wiring. At that time I did try to find the plug, but there was nothing even remotely resembling it.

Let me take some snapshots of the carb tomorrow It has low flowing vacuum ports and high flowing ones. I'll outline that with pictures tomorrow.

One of the high-flow ports I had assigned to the distributor when I re-did the vacuum system (there was not one hose connected in the car when I bought it.... in fact finding a vacuum chart was the very thing that got me looking for online assistance, and landed me here in the first place).

The sensor marked as #1 in the other thread, is with 2 wires. Where the wires end up I have no idea (as of now).

85_Ciera_Rebuild
01-06-2008, 04:07 AM
The sensor marked as #1 in the other thread, is with 2 wires.

Assuming distributor's wires (via 3 spade side of module) and these 2 sensor wires are hooked to a little box (ESC control module) and this 2-wire sensor is a working knock sensor,

then while the motor is running (idle), lightly tap with a hammar (or wrench) near this sensor (#1)....if everything is working, and it is the knock sensor, there will be a change in engine R.P.M.

85_Ciera_Rebuild
01-06-2008, 04:11 AM
The ALDL plug


Check with your local GM dealership, since with the VIN, they should be able to tell you which motor was originally in this vehicle.

If no ALDL plug existed, then there was no computer (unless they stuck ALDL plug in engine compartment)....but why the "Service Engine Soon" light should come on, is a mystery.

PS: Refresh my memory, which city/country are you in?

Tuddi
01-06-2008, 05:21 AM
Lima-Peru-South America
One or another day I will have a closure on the origins of the engine in the car... not quite now though.

Meeting tomorrow sunday (well, that's today)... another meetings monday and tuesday... software devellopment ongoing panophotos in need to be shot and processed.

.... the car goes far down the list again.

Tuddi
01-06-2008, 05:23 AM
Assuming distributor's wires (via 3 spade side of module) and these 2 sensor wires are hooked to a little box (ESC control module) and this 2-wire sensor is a working knock sensor,

then while the motor is running (idle), lightly tap with a hammar (or wrench) near this sensor (#1)....if everything is working, and it is the knock sensor, there will be a change in engine R.P.M.

Ah... !! I'll try that in the morning! Thanks for the tip!

85_Ciera_Rebuild
01-06-2008, 06:07 PM
the tip!

Here's another tip...

Dcjredline cited this URL (http://www.cadillacforums.com/forums/cadillac-forum/t-50062.html), which gives timing spread for two different distributors:

Example:
.
Base timing:-->10 degrees
Mech Adv:--->24 degrees
Total Adv:--->34 degrees
.
Modified with EMR
.
Base timing:-->20 degrees
Mech Adv:--->14 degrees
Total Adv:--->34 degrees

As this author noted correctly: "I recommend that cars with vacuum advance, that you use the timed vacuum port and do not use full time vacuum (which always was the crutch for many cars with limited low rpm timing)."

Timed vacuum port means the port on the carburetor that does not have a vacuum at idle RPM, but this vacuum port increases with vacuum as the throttle is depressed.

Consequently, since it appears your Vacuum Advance pot is not working, your engine is not getting its full horsepower, nor will it get its full m.p.g. (miles per gallon).

Your engine most likely is running a flat timing, with no timing advancement when the vacuum advance is not working. Further, when your vacuum advance is working, this is when your knock sensor comes into play; as the timing is advanced, if there is any pinging, your knock sensor will back off the amount of timing advanced it has given to engine. Your knock sensor needs to be working when the vacuum advance is working for this vehicle (assuming this is a ESC ignition system, which I suspect it is).

PS: Great weather down there (http://www.wunderground.com/history/airport/SPIM/2007/1/6/CustomHistory.html?dayend=6&monthend=1&yearend=2008&req_city=NA&req_state=NA&req_statename=NA) in Peru...oh, how a person could get spoiled.

Tuddi
01-06-2008, 08:28 PM
Scheduled meeting was delayed, and I got out to the car, hitting the area around the sensor with a hammer like a mad-man... and nothing changed in the engine, so either it's not a knock sensor, or it's dead.

But in yet another attempt to have the idle improved, I unplugged both batteries, loosened the distributor, threw the spanish switch (the one used for adjusting the timing) to the "adjust time" position. Reconnected the batteries, started the engine, adjusted the timing until I was relatively pleased with it running idle and revving it. Threw the switch back to "normal" ... test drove it, and it was quite ok. The idle is much better now than what it was yesterday, and I had to concentrate on trying to hear any change in the engine running... I THINK it's a little bit in non-compliance with my wishes, but I'm not sure.

I do have to take the valve covers off and tighten the rods in order to eliminate the current knocking going on, and that should improve the idle as well.

We are indeed lucky with the weather in the summertime (now) ... it never gets really cold here, but the humidity is terribly high all year round. Coming from icy Iceland to here, was a major change of climate. Christmas holidays in baking sun isn't something I was raised up with as being anywhere close to normal.

85_Ciera_Rebuild
01-06-2008, 10:50 PM
But in yet another attempt to have the idle improved, I unplugged both batteries, loosened the distributor, threw the spanish switch (the one used for adjusting the timing) to the "adjust time" position. Reconnected the batteries, started the engine, adjusted the timing


Timing is normally adjusted via loosening a bolt on the distributor's "neck," and then rotating the distributor while using a timing light focused upon harmonic balancer when the engine is at an idle, and the vacuum hose to advance pot (on distributor) is disconnected and plugged.

Both Batteries - Only one is needed...apparently law enforcement had two.

Spanish Switch - This may be some after-market device....with some "voodoo" properties. Maybe a quick fix when the stock GM part failed.

Note - This Spanish switch needs to be investigated....can you find one on the internet? It may be by-passing the ESC circuit....where do those wires from the 3-spaded side of distributor's module go...do they go to this Spanish switch or....its box.... These 3-spaded wires need to be traced....I suspect strongly there was an ESC Controller Box....but it appears with this Spanish switch you can change the timing, which means this was not STOCK GM.



PS: Have you spent anytime in Chosica Peru? Nicer weather? Seen any URLs on this town?

Tuddi
01-06-2008, 11:20 PM
That's the bolt I loosened of course, and the 2 batteries is something I did. The old battery was quite ok, but didn't hold much of a punch, so I bought a new Bosh 70 amp battery, and after a long time I put the old one in as well. I won't run out of juice even if the car beahves badly for a while.

The "Spanish switch" (let's call it "SS") was also present in another Celebrity I have checked out and (still) want to buy. Both mine and that other Celeb were registered on the same day 22 years ago, and both were used by the Police forces here.

If I flip the SS on "adjust timing" give the engine some gas so it is not idling, and while doing so, flip the SS to "normal, let go of the carb so it will go to idle... the engine will run terribly and stall. If I flip the SS to normal when the engine is idling normally, it will be ok. So this works... whatever it is :)

I have not been to Chosica... that I remember... mostly I go to the jungle when I go outside Lima.

85_Ciera_Rebuild
01-07-2008, 01:42 AM
The "Spanish switch" (let's call it "SS")


Ignition System - There are two potential ignition systems that could have been installed by GM. One of them is without the Knock Sensor (EMR: which used a vacuum switch to retard the timing), and the other would have this knock sensor (ESR). If this vehicle has the EMR system, then this switch could be sending a ground (or a hot voltage, I would have to look this up) to the "retard" spade on distributor's module.

Only point here is if I know which ignition system is on this vehicle, then I can get specific info on it....and then you will understand it. I can trouble shoot this vehicle, but I need to know its parts...I suspect the actual problem lies elsewhere, but its important to have your electrical side working first.

I might add that all electrical wires should be inspected/cleaned, where possible. With the high humidity there, rust/etc will cause problems. The distributor's electrical connections (grounds) looked like they needed to be cleaned up. Even the vehicle's ground strap to the engine should be cleaned up.

"Knock Sensor" - If this sensor has a number on it, maybe you could ask GM Parts. I assume you know where the Oil Pressure Sensor is, and the Temperature Sensor is?

Instrument Gauges - Are there idiot lights, or analog/digital displays on dash?

Push Rods - I assume you know how to make rocker arm adjustments.

Engine - 2.8 motors of 1985 era had a problem with oil pumps....the screen would get plugged up, and oil starvation was end result. Idiot light does not go off till around 6 p.s.i., which at highway speeds is not enough oil pressure. Unless one knows this engine's history, it may be worth the time to drop the pan, check out a few bearings, and change out oil pump.

Also, I rather doubt if GM made any special engines or electrical systems just for export markets...my gut feeling is they used existing products and had variations in each model year. Since pollution control would not have been relevant in Peru, I would suspect they installed previous years equipment into your vehicle.

Oil Pressure Sensor - If GM had a fuel pump in gasoline tank, GM would have used in U.S. an oil pressure sensor that had three wires going to it....FYI.

mickstan_VR
01-07-2008, 01:45 AM
The spanish switch? wtf??? I don't understand. Tuddi, take some pictures of this mystery device!

Tuddi
01-07-2008, 02:03 AM
http://upload.hraunfjord.org/files/IgnitionSwitchVacUnit.jpg

http://www.a-body.net/forums/showthread.php?p=3994#post3994

85_Ciera_Rebuild
01-07-2008, 02:46 AM
SS Spanish Switch

What is the device on SS's left side? Are its wires connected to this SS?

Tuddi
01-07-2008, 03:03 AM
It's a vacuum valve of some kind. I connected it to the carb vacuum, and it all seems to be working... somehow... someway.

85_Ciera_Rebuild
01-07-2008, 03:48 PM
It's a vacuum valve of some kind.

If it has electrical wires that are connected to ignition system (via box that then goes to distributor), then this vehicle would not have a Knock Sensor, and it would have an ignition system like EMR (Electronic Module Retard)

I don't have the time to read theoretical underpinnings, but I found another ignition system called:

Electronic Spark Selection (ESS) System that was found (in US) on some 1978-80 Cadillac Models.

Guess what, this has a distributor with a module that has "H-L-D" imprinted upon it...same letters as in this picture of yours here (http://upload.hraunfjord.org/files/DistInside.jpg).

Would you like to know something about this ignition system?

My Note - Page 139 in Mitchell Manual

85_Ciera_Rebuild
01-07-2008, 05:16 PM
Note - Cadillac setup this ESS system in different ways. I found this URL interesting (http://www.cadillacseville.org/index.php?option=com_content&task=view&id=106&Itemid=16).

But, I rather doubt your system has the same features (indicator lights/etc). But, this description only gives a sense of this system.

In Mitchell Manual, they show the essence of it, so the mechanic can fix the electronic side of it...this manual shows "H-L-D" letters, but in the reverse order as on your module. So, either the artist reversed it....or a different module.

But, this manual talks about the 3 possible timing positions....which using a SS could place it in the Retarded Position....which would be used for timing ignition purpose only...I must assume.

On a Cadillac, they disconnect the ESS Decoder, which places the timing at 6 degrees higher. Since your vehicle is of a later vintage, this SS may have served the same purpose; instead of disconnecting ESS Decoder's plug, you flip a switch (SS).

As you may know, all vehicles need to be timed correctly, and once you do it, you don't mess with it, again, and again. For these vehicles, using a timing light is a must, imho.

Tuddi
01-08-2008, 04:28 AM
For these vehicles, using a timing light is a must, imho.

Thank you very much for giving so much of your time to this issue.

Yes, a timing gun is the only way to tune a car (like mine) properly. I only have one more problem that makes that impossible right now.

My Harmonic Balancer was in 3 parts, and there is no telling which position the time mark on it should be in. I need a new H-B and the engine support that is under it. Haven't got to order those pieces yet... time is too limited to remember everything all the time... (that's a recipe for mechanical breakdowns... I know...)

So a fine tuning of the engine is out of the question as it stands. The best I can do, is to listen and feel my way to the "best" result.

The tuning I did the day before yesterday ... or was it yesterday? ... don't remember... proved itself out of tune today. When switching off the engine, it kept on running erratically for a few seconds. Obviously way off on the ignition.

85_Ciera_Rebuild
01-08-2008, 06:36 AM
My Harmonic Balancer was in 3 parts, and there is no telling which position the time mark on it should be in.


Yes there is....a dial indicator is needed in spark plug hole #-1...bring piston one up to TDC...



When switching off the engine, it kept on running erratically for a few seconds. Obviously way off on the ignition.

I think this vehicle's plugs were upgraded one heat range....but timing being off can induce more heat...throttle plate's position might be involved in this equation...one can leave it in gear, and then turn off ignition...but turning the distributor to reduce the extra advance in it (I assume) might work too...one has to retard it back a pinch when it increases RPM...I do not think using the SS is required for shade treeing.



So a fine tuning of the engine is out of the question as it stands


As you know...it all starts with correct timing....in earlier years, they were conservative in dynamic range of timing...then with knock sensors, they increased timing's dynamic range....more and more with further ECM refinements.

With ESS, you could get better highway mileage in that era....since timing was changed with highway driving...that vacuum switch is what controls this feature. There could be a temperature switch for this ESS system also, which controls cold starts.

When you get time, I'll give it my best shot if asked. If there is an interest, I could get those two pages scanned, and upload them to your web-page drop-off in several days. My email address is legit, so if you have other questions, feel free to ask; I'm familiar with this older stuff...just need to know what stuff you have. We didn't get to the Carb yet, but I think I cited two tidbits of information concerning vacuum ports, and distributor's vacuum advance needing repair.

Tuddi
01-08-2008, 07:39 AM
Aaarggghhh.... yes, the carb pictures I promised to take. Sorry mate! I've been too busy with everything else to remember.

I am interested in all material that can get me closer to having all needed documentation for the car. After all the car holds the key to my family's life when they are in it with me... so I want it safe and secure and in a failfree working condition... meaning that if it's not too much bother for you to make the scans, it would be very well received on this end!

I think the ignition is supposed to be at 10° BTDC (easily figured out with a timing gun if the Harmonic Balancer had not been in 3 parts... )

You say I should have cyl#1 up to TDC... then I assume I should check with the ignition (distributor hammer's position relative to #1 distrbutor cap's contact). But wouldn't that be TDC timing, and not the 10° BTDC it should be?

And today's stupid question: If I turn the distributor clockwise (after loosening it's neck-tie-bolt), am I advancing the timing or retarding it? I vote for "advancing"... but I'm getting too rusty on these obvious issues after having only Diesel SUV's during the past 10 years before moving to Peru, which I did 7 years ago, and had no car until the Bluesmobile which I bought last may.

Before all of that, I had not been working on cars in any real sense since 1984... so please bear over with my rusty ignorance :)

dcjredline
01-08-2008, 01:43 PM
I havent seen any mention of it in the prior posts and it may mean nothing to anyone but acording to the VIN this car was made in Canada VIN starting with 1 are Canada and VIN starting with 2 are US models. Again I dont know if this may have anything to do with this just thought I would add it.

85_Ciera_Rebuild
01-08-2008, 04:05 PM
I think the ignition is supposed to be at 10° BTDC..

What would be done here is to use this method to find TDC (http://www.wikihow.com/Find-Your-Engine's-Top-Dead-Center-(TDC)) so that TDC can be marked on the Harmonic Balancer. Then after TDC has been marked on Harmonic Balancer, then you use a timing light to find correct timing when the engine is running.

This author also mentions this method: "You can also use a soda straw sticking out of the sparkplug hole. Trouble is that there are several degrees of crankshaft rotation where the piston remains stationary." A dial indicator can work also, but you have to be careful when using a dial indicator when the head is not removed; see this explanation (http://www.cadvision.com/blanchas/54pontiac/tdc.html).

When doing any of these methods to find TDC, number one piston must be coming up on compression stroke....and they describe how to use your thumb to make sure number one piston is coming up on compression stroke.


If I turn the distributor clockwise


I always use a timing light...but the distributors in different engines could work in opposite directions, due to how they have the gears setup...so I can't answer this question for your vehicle...but, if the engine RPM is increasing as you turn distributor, you need to turn it the other way to retard it. There is a range here, from too much retard to too much advance, but when going from retard side to advance side, the engine will increase in RPM... But, with a Timing Light, and a timing-indicator near harmonic balancer, you can figure out which way the distributor rotates for advance/retard if the harmonic balancer has a TDC mark on it. I don't suggest using this shade-tree method...buy a timing light, or find a mechanic with a timing light, and have him find out which way to rotate the distributor. I know how to do this as a shade-tree method, but I use a timing light.

85_Ciera_Rebuild
01-08-2008, 04:10 PM
It appears Dcjredline in post # 33 is not seeing my posts, could someone cite this below to him? Just copy/paste it.

Thanks...


1. "In North America, GM uses universal three-character alphanumeric RPO codes to refer to a specific car option, including engine model.
...
...
GM LAAM (Latin America, Africa and Mid-East) and GM Europe uses four- to six-character SKU codes, such as CN22E, to represent family, displacement and engine features."

http://en.wikipedia.org/wiki/List_of_GM_engines

Tuddi
01-08-2008, 06:21 PM
It appears Dcjredline in post # 33 is not seeing my posts, could someone cite this below to him? Just copy/paste it.

Thanks...


1. "In North America, GM uses universal three-character alphanumeric RPO codes to refer to a specific car option, including engine model.
...
...
GM LAAM (Latin America, Africa and Mid-East) and GM Europe uses four- to six-character SKU codes, such as CN22E, to represent family, displacement and engine features."

http://en.wikipedia.org/wiki/List_of_GM_engines

Thanks for great information on finding and marking up the new TDC on the HB. This I will do (when I get the time for soiling my hands again)

dcjredline
01-08-2008, 07:43 PM
It appears Dcjredline in post # 33 is not seeing my posts, could someone cite this below to him? Just copy/paste it.

Thanks...


1. "In North America, GM uses universal three-character alphanumeric RPO codes to refer to a specific car option, including engine model.
...
...
GM LAAM (Latin America, Africa and Mid-East) and GM Europe uses four- to six-character SKU codes, such as CN22E, to represent family, displacement and engine features."

http://en.wikipedia.org/wiki/List_of_GM_engines

If youre trying to be an asshole to me its working. I see NO WHERE in your first post of it OR the post you just tried to be a D*&K in stating ANYTHING about the 1st digit of the VIN #. Your post is talking about options and RPO codes I was talking about where the car was built. NICE TRY!!!! :mad:

85_Ciera_Rebuild
01-08-2008, 11:31 PM
I was talking about where the car was built.

If this post here is read (or re-read) (http://www.a-body.net/forums/showpost.php?p=3935&postcount=9) , it is explained where the vehicle was manufactured in the third paragraph.

Vin X has no meaning, in regards to engine size, that I am aware of...in 1985 era. Vin "R" would if this engine was installed in this vehicle.

If his VIN can be deciphered in terms of knowing which engine came with this vehicle....this would be greatly appreciated. Its beyond what I can find out about it.


Neat Videos: These movies are all taken with Phantom high-speed cameras.
(http://www.visionresearch.com/index.cfm?sector=htm/app&page=Gallery)

85_Ciera_Rebuild
01-09-2008, 12:39 AM
....10° BTDC....

As noted in this article (http://www.tpub.com/content/construction/14273/css/14273_67.htm), there are three ways to advance timing:

1. CENTRIFUGAL ADVANCE (controlled by engine speed)

2. VACUUM ADVANCE (controlled by intake manifold vacuum and engine load)

3. COMPUTERIZED ADVANCE (controlled by various sensors—speed, temperature, intake, vacuum, throttle position, etc.)


In older US consumer vehicles (pre 1980 era), only items one and two were used. Then, after 1980, they may have used all three methods. And finally, they went to computer only doing the timing advance.

Your vehicle uses all three, but most likely, your vacuum advance is not working.


Distributor - Your distributor has both centrifugal and vacuum advance mechanisms within it...but your vacuum advance is not working.

As noted in this article about a distributor's vacuum advance (http://www.tpub.com/content/construction/14273/css/14273_67.htm):


At idle, the vacuum port from the carburetor or throttle body to the distributor advance is covered, thereby NO vacuum is applied to the vacuum diaphragm, and spark timing is NOT advanced. At part throttle, the throttle valve uncovers the vacuum port and the port is exposed to engine vacuum. The vacuum pulls the diaphragm outward against spring force. The diaphragm is linked to a movable distributor plate, which is rotated against distributor shaft rotation and spark timing is advanced. The vacuum advance does not produce any advance at full throttle. When the throttle valve is wide open, vacuum is almost zero. Thus vacuum is NOT applied to the distributor diaphragm and the vacuum advance does NOT operate.

So, the vacuum advance smooths out your engine while running in mid-range RPM range, and your vehicle is missing this additional timing advance.

With a timing light, a good mechanic can check to see if both CENTRIFUGAL ADVANCE and VACUUM ADVANCE are both working.

Shade Tree Timing Adjustment - Again, I've always use a timing light, but as noted before, I think your ignition timing is advanced too far. You could try to adjust timing, but engine RPM will decrease on both retarding/advance sides. But, if you can find a center position where engine RPM is about right for idle, then slow engine RPM down just a pinch...if distributor is turned in opposite direction, engine RPM should increase...so the trick is too slow it down a pinch. But, your engine's mid-range RPM may have driveability issues...maybe not as quick, when the timing is set right...due to your vacuum advance not working.

I've got those two pages about ESS ignition system that are copied into two PDF files ( One Meg total)....could you cite that upload URL again?

85_Ciera_Rebuild
01-09-2008, 01:09 AM
.....10° BTDC....

Vacuum Advance: (http://www.2quicknovas.com/happytiming.html) Vacuum advance is controlled by the canister that's on the side of the distributor. Its function is to provide extra advance at high vacuum to increase fuel economy. The amount of advance can be adjusted by swapping on a different vacuum canister or by putting on an aftermarket adjustable canister. Also, where you have the vacuum line hooked up affects the vacuum advance. Ported vacuum (above the throttle blades, usually on the side of the carburetor) gives you no advance at idle and increasing advance (to a point) as the throttle opens. As the throttle approaches wide open, the vacuum goes away and so does the vacuum advance. Full manifold vacuum takes its signal from below the throttle blades and is highest at idle and gradually drops to zero at WOT. Full manifold vacuum generally isn't used except for some factory stock applications, and even then it's often not a good idea.

NOTE - On your vehicle, use the stock GM replacement for automatic transmission; this info above is for hot-rodders when they change stock parameters.

Tuddi
01-10-2008, 02:55 AM
Thanks again, it is very helpful info you have dug up for me.

85_Ciera_Rebuild
02-01-2008, 01:13 AM
it is very helpful info you have dug up for me.

Your welcome...check your upload site for:

user file name: ess2.jpg

and

user file name: ess.jpg


Rename them to PDF file format:

ess.pdf

ess2.pdf

and take a look.

Tuddi
02-01-2008, 01:28 AM
my upload site is HERE (http://upload.hraunfjord.org/upload.php3)

But there is nothing there named either ess.jpg (http://upload.hraunfjord.org/files/ess.jpg)or ess2.jpg (http://upload.hraunfjord.org/files/ess2.jpg)

Now you got me curious! :eek5:

85_Ciera_Rebuild
02-01-2008, 03:04 AM
upload site


File is located in tmp, phpBvCVug directory, and is called: Rename_PDF.jpg (http://upload.hraunfjord.org/files/Rename_PDF.jpg)

Tuddi
02-01-2008, 05:46 AM
Ok, that did it! Found both and saved them to the ignition category I have for the car.

Thanks a bunch!