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TheDeuce
03-13-2008, 05:40 PM
Ok, I have an '85 6000 STE and I posted this thread (http://www.a-body.net/forums/showthread.php?t=532) about replacing my oil pressure sensor, because recently it seems I'm getting less oil pressure.

Typically, when I fire it up, the oil pressure is somewhere between 40 and 60 or so psi, depending on how cold it is outside {its been warming up around here, but there were some days in the last few months where it was like 10 degrees}. Then when it warms up it sits around 40 while crusing and might drop slightly. Now once it warms up it sits at 40psi while crusing, and drops to 3 dashes on the digital display at idle, when warm. I replaced the oil pressure sensor and now once warm, it was idling at about 2 dashes. While going through the fun of backing into my driveway it actually dropped to zero and stalled out after a short 30 minute trip.

A few weeks ago I had to clean my idle air valve because of stalling at warm idle and it fixed the stalling. Could it just be a bad Idle air valve that makes it have lower oil pressure at idle or could it be something worse? There's no squealling or any other sounds from the engine when it drops or anything. Could there be anything more seriously wrong here like, God forbid, the oil pump dying? Or am I worrying for nothing?

Also, after cleaning the idle air valve and/or replacing the oil pressure sensor, should I have reset by pulling the negative cable?

Pontiac6ksteawd
03-13-2008, 06:14 PM
My STE AWD has always had oil pressure like that, without the stalling issues, since I have owned it. Been close to 35000 miles, and 5 years. And no problems yet. As long as your oil pressure light doesnt turn on, I probly wouldnt worry about it to much. I have seen these 2.8 and 3.1's take some major abuse. Being ran with no oil until the motor locked up. Putting new oil in, letting it cool off, starting it up, with not a single problem.

dcjredline
03-13-2008, 06:17 PM
Mine did the same thing too when it was actually running.

LordDurock
03-13-2008, 07:00 PM
some oils just do that. just as long as you have oil persser. you shoud be good

85_Ciera_Rebuild
03-13-2008, 08:07 PM
should I

Get some Shell Rotella 15W40 T from Walmart...get it a try.

CieraSL92
03-14-2008, 02:27 AM
Get some Shell Rotella 15W40 T from Walmart...get it a try.


That might be too thick for winter.. Just an opinion.

TheDeuce
03-14-2008, 05:39 AM
See, I don't know if I'm focusing on the oil pressure because that's the thing that's easily noticable. What happens is that once the motor is up to 190 degrees {or whatever the middle temp of the guage is}, when I come to a top like at a light or stop sign or just in a parking lot, the oil pressure goes down to like 2 dashes and it seems like it wants to stall, or does as was the case this afternoon. The revs go down to near the bottom as well, but I figure that would be expected as I am coming to a stop.

It will be oil change time in about 1000-1500 more miles, and in spring/summer I usually run 10W30 as opposed to the 5W30 in the winter.

85_Ciera_Rebuild
03-14-2008, 05:57 AM
goes down to like 2 dashes...10W30...5W30

How many total dashes...maybe 12 ?

My 2.8 motor, when I bought it (vehicle) was running at 2 bars, which for 88 Beretta, is about 10 to 12 psi...the minimum in my book. There was sludge in bottom of pan, and I suspect oil pump was by-passing since gears were good.

At highway speed, how many bars are there?

5w-30 and 10w-30 are the same when engine is at temperature....no difference...if you aren't going to change oil pump, try some 15w-40...or 10w-40.

TheDeuce
03-14-2008, 06:59 AM
How many total dashes...maybe 12 ?

My 2.8 motor, when I bought it (vehicle) was running at 2 bars, which for 88 Beretta, is about 10 to 12 psi...the minimum in my book. There was sludge in bottom of pan, and I suspect oil pump was by-passing since gears were good.

At highway speed, how many bars are there?

5w-30 and 10w-30 are the same when engine is at temperature....no difference...if you aren't going to change oil pump, try some 15w-40...or 10w-40.

yeah, 12 or 14 {its 2am right now, so I'm not going out to check it}. At crusing speeds its 40 PSI, 6 or 7 dashes. When it was dropping to 3 or 4 dashes I got concerned, but figured it was still about 10 or 15 PSI, which would be fine. But today it was going down to 2 dashes, and eventually 1 when it stalled out backing it in the driveway.

The thing is that I'm worried about the stalling & if it happens again. Doing it it my driveway is one thing, on a busy street is another. I keep bringing up the Idle Air Valve because I had some stalling problems a few weeks ago and my buddy who's sort of a mechanic told me to clean it off because he had a similar problem. Everything was good until about 2 weeks ago, when after I had to replace a brake hose on the front tire that broke all this drama started.

mickstan_VR
03-14-2008, 09:10 PM
Sounds like your idle speed is too low for some reason. As it idles down, the oil pressure will get less and less. If it idles sooo low that its ready to stall, then yes the oil light will flicker on. I think the IAC is out of whack or something, or you got a vacuum leak.
Which motor are we talking about here?

LordDurock
03-14-2008, 09:21 PM
^that could very well be the 85's ware carbed right

Pontiac6ksteawd
03-14-2008, 10:03 PM
It could be either. They had the 2.8 Gen 1 MPFI option, standard was the 2.8 Carb I THINK.

CieraSL92
03-15-2008, 12:02 AM
5w-30 and 10w-30 are the same when engine is at temperature....no difference...if you aren't going to change oil pump, try some 15w-40...or 10w-40.

..Who cares about at temperature thickness? I was referring to when the oil's thick and the engines cold. It will exercise the starter, and may not start if your battery's not up to it.

'Bar' guages are useless except for relative change. Connect a real pressure guage to the oil sending unit port.. Of course if the engine is not at idle, this will cause low oil pressure, meaning any reading is useless unless its idling correctly.

85_Ciera_Rebuild
03-15-2008, 12:04 AM
At crusing speeds its 40 PSI, 6 or 7 dashes.


Seven, on 88 Beretta, is at centerpoint of the bar scale. I only did two calibration points on my setup...at 30 psi, this was 5 bars, and at 60 psi, this was 9 bars. So, each bar represents about 6 to 6.7 psi.

With 5w-30 oil in cooler weather (have not driven vehicle in hot weather yet), I'm running 8 bars at 40 mph or so...at hot idle, 3 bars...but this is a 166,000 mile motor with new oil pump on it.

I think there are 14 total bars on this 88 Beretta, and on a cold morning, if I gently bring it up to 3,000 RPM after a cold start, with 5w-30, I can light up all 14 bars.



when after I had to replace a brake hose on the front tire that broke all this drama started.

Get a can of starting either, and spray around engine compartment....you might pull off some vacuum lines (brake booster, etc), and see what happens...might use a vacuum guage and see what your intake vacuum is.

TheDeuce
03-15-2008, 02:38 PM
Which motor are we talking about here?

2.8, Fuel Injected.

Pontiac6ksteawd
03-15-2008, 10:24 PM
The first gen 2.8 MPFI were a vacume line nightmare. Start with starting the car with the hood raised. With a spray can of carb cleaner, with the tube on, start spraying around the intake plenum, all the vacume lines, and listen for any change in idle. if the idle changes, you Found the vacume leak.

85_Ciera_Rebuild
03-16-2008, 06:47 PM
I was referring to when the oil's thick and the engines cold.

Here's a chart (http://apps.volvocars.us/ownersdocs/1984/1984_DL_GL_and_Turbo/images/pg60a.jpg), but yes, in more colder environments, 5w-20 or 5w-30 is more desirable.

On my next oil change, I plan to try 15w-40 Roto T, for the heck of it.

Currently, when running down the highway in cooler weather, I'm most likely blowing the by-pass open since oil pressure never exceeds 60 psi when going down the highway with engine upto temperature. So, even if I have 15-w40 in there, the by-pass will still be opened.

TheDeuce
03-17-2008, 03:33 PM
so, I was thinking of trying to look for a possible vacuum leak. I want to defer to the expertise of you guys here and ask if there are any common occuring culprits before I haphazardly start poking around. Is there one or more lines that more frequently leak? Here's a diagram of what I got-
http://img119.imageshack.us/img119/4923/0900823d800f1dc1sz2.th.jpg (http://img119.imageshack.us/my.php?image=0900823d800f1dc1sz2.jpg)

Also, I'm not sure if this is related, but I'll throw this out there, but yesterday I was out in my ride and some jackass was tailgating me, so I had to take a hard right turn down the street I was turning on to avoid getting hit by this guy and when I did the Check Engine light came on. I stopped, turned the car off and then back on, and it went off. Like I said, not sure if its related to the problem I have, or if it just went on because everything sloshed to one side due to the turn and set it off.

85_Ciera_Rebuild
03-17-2008, 08:02 PM
..look for a possible vacuum leak


What is check engine light code?

1. Read this thread: http://www.a-body.net/forums/showthread.php?t=497&page=3

2. What weight of motor oil do you have in it?

TheDeuce
03-18-2008, 04:42 AM
What is check engine light code?

1. Read this thread: http://www.a-body.net/forums/showthread.php?t=497&page=3

2. What weight of motor oil do you have in it?


Not sure of the code. My sister's boyfried has a code checker and she's bringing that over tomorrow. But I've seen some talk on here of a paperclip test. Fill me in on that and I'll check it tomorrow. I'm assuming that you put a paper clip in the ground and the lead next to it, as I've had my buddy read codes off with what I like to call "The Magic Key" {I know, I need a life}.

Oil is 5w30.

85_Ciera_Rebuild
03-18-2008, 05:03 AM
paper clip...Oil is 5w30.

In that thread, bodega1027 cleaned out his EGR valve and tested it...do the same.

Oil, you might use 10w-30, unless you live in a really cold environment...my 2.8 engine would "hunt" with lighter oils....they are more slick today, than in 1988.

How to read older GM OBD diagnostic codes for free (http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php)

TheDeuce
03-18-2008, 05:13 AM
In that thread, bodega1027 cleaned out his EGR valve and tested it...do the same.

Oil, you might use 10w-30, unless you live in a really cold environment...my 2.8 engine would "hunt" with lighter oils....they are more slick today, than in 1988.

How to read older GM OBD diagnostic codes for free (http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php)

Thanks for the tips.

Yeah, I typically run 10w30 in the spring/summer/early fall and 5w30 in the winter. Its been pretty cold around here this winter, going to below zero at some points in january and february. Its due for an oil change in about 500-1000 miles or less and I will put 10w30 in at that point.

TheDeuce
03-19-2008, 05:52 AM
In that thread, bodega1027 cleaned out his EGR valve and tested it...do the same.

I'm going to clean out the EGR tomorrow, as today was not a good day to be working on cars {cold, rain all day, very cloudy and dark}. My new question is if its safe to use carb cleaner on th EGR. I have the non digital kind, the diaphram kind. I just wanted to make sure that using carb cleaner wouldn't mess up any of the inner workings or the diaphram.

Also, I checked for codes this morning using an bit of wire to ground the diagnostic lead and there were no codes stored. Just flashed the 12 {or is it 13?} working code.

85_Ciera_Rebuild
03-19-2008, 05:59 PM
...EGR...safe to use carb cleaner...non digital kind, the diaphram kind.


On this kind of EGR, I push up the diaphragm, and spray Carb Cleaner in passage ways. Let it sit for say 10 minutes, and do it again...then I would blow it off via air....with diaphragm held up. Needless to say, I look at it for carbon deposits, then clean them off.

I also get a vacuum hose and attach it to EGR vacuum port, suck on this hose, and stick my tongue on hose, and see if EGR diaphragm holds a vacuum.

If there are no codes, there is a good chance EGR is working fine.

If you can find a vacuum gauge, you might see what your vacuum is at idle.

85_Ciera_Rebuild
03-19-2008, 06:12 PM
no codes stored. Just flashed the 12 {or is it 13?} working code.

How many times did you see Code 12? If you saw it more than four times, then no codes are present.

It flashes Code 12 several times, then if codes are present, it will then flash them.

Hence, after several flashings of Code 12, then if a problem(s) exist, those codes will come up.

TheDeuce
03-19-2008, 07:04 PM
How many times did you see Code 12? If you saw it more than four times, then no codes are present.

It flashes Code 12 several times, then if codes are present, it will then flash them.

Hence, after several flashings of Code 12, then if a problem(s) exist, those codes will come up.

Ok, so I didn't realize that the 12 would flash 3 times first, so I did it again. I got a code 34. What's the diagnosis for this?

Also, I haven't even messed with the EGR. I was going to, but the bolts seem too rusted and I'm worried about cracking them. I'd rather do it when I have access to another car {my old man's} and a little bit of a hand.

However, should I even bother now that this code 34 has come up, or could that just be stored from my hard turn the other day?

Pontiac6ksteawd
03-19-2008, 07:15 PM
I beleive thats the MAP sensor code.

TheDeuce
03-19-2008, 08:05 PM
I beleive thats the MAP sensor code.

According to the repair manual freshly taken out of the library, it is. However, this great book doesn't tell you where its located at. So, where can I find this beast?

85_Ciera_Rebuild
03-20-2008, 04:58 AM
EGR...but the bolts seem too rusted

Take a punch, place it in center of bolt, and whack it (punch) with a firm hammer blow.


code 34 has come up

Code 34 is either a MAF or MAP sensor......earlier 2.8 had a software update and were using MAP sensor via speed density software. If your vehicle has a MAF sensor, it may not be used by ECM, if you have Speed Density software.

There is a way to bench test your MAP sensor (read this) (http://www.wellsmfgcorp.com/pdf/Counterpoint1_1.pdf)

Do you have a working MAF sensor on your vehicle...it would be a tube shaped thing hooked into air intake...got a picture of your motor?

MAP sensor may be located around firewall...look at this site (http://www.autozone.com/shopping/repairGuide.htm)..they may show where it might be located.

TheDeuce
03-20-2008, 05:29 AM
[QUOTE=85_Ciera_Rebuild;6079]Code 34 is either a MAF or MAP sensor......earlier 2.8 had a software update and were using MAP sensor via speed density software. If your vehicle has a MAF sensor, it may not be used by ECM, if you have Speed Density software.
Do you have a working MAF sensor on your vehicle...it would be a tube shaped thing hooked into air intake...got a picture of your motor?

MAP sensor may be located around firewall.../QUOTE]

I do have a MAF sensor. I'll take some photos tomorrow, but right now its probably too dark as it is 20 after midnight.

I took a look at the autozone location thing and I think I have a good idea of where it would be. Again, I'll have to check when its light out.

Thanks for the bench test. I'd like to test it before throwing down cash on a new one without knowing if it is really messed up.

A couple years ago I was having some issues with the car not starting right away, it took a few cranks to get it to go and the check engine light would come on. I got the codes read and I remember at that time that there was one code for the MAP, which was probably the #34, and I think there was a separate code for the MAF. i could be wrong though as it was a few years ago. The problem at the time ended up being a relay that was not working right, after replacing that and clearing the codes there were no other problems

TheDeuce
03-20-2008, 05:08 PM
Code 34 is either a MAF or MAP sensor......earlier 2.8 had a software update and were using MAP sensor via speed density software. If your vehicle has a MAF sensor, it may not be used by ECM, if you have Speed Density software.

Did some poking around this morning and I cannot seem to find a MAP sensor, using the autozone component locator, which says, "Under hood, passenger side, upper engine area, passenger side end of air intake hose, mounted rear of air filter housing". There is nothing there. Is there even MAP sensor on the '85 6000 STE? I went up to the local autozone that my friend works at and asked them to look up the code and they said that its probably the MAF. I just now cleaned up the leads and the wiring harness from the dust and crap on it and I disconnected the negative to reset the system. I'm just about to go back out and reconnect the battery and check it out again.

Is it possible to take the MAF sensor off and clean the inside part up? I've heard its a fragile sensor, so I don't want to do more harm than good by messing around with it.

85_Ciera_Rebuild
03-20-2008, 06:28 PM
MAP sensor

Is it possible to take the MAF sensor off and clean the inside part up?

Following those smaller vacuum lines on intake manifold to where they go...you may find a MAP sensor with three wires on it,,, rectangle small box shape.

Yes, there is a specific cleaner for MAF sensor....but, if your vehicle has the Speed Density update in it, the ECM does not use the MAF sensor anymore....they had a real production problem in the early days with MAF sensors....my 88 Vehicle has Speed Density update, and does not use the MAF sensor...its there, but not used.

85_Ciera_Rebuild
03-20-2008, 06:42 PM
MAF sensor

Let me check my 2.8 motor's code...I think it always has a Code 34, but that's because of speed density software....

Do not buy a MAF sensor...check again to see if you have a MAP sensor.

Also, look for a sticker on shock towers that says Speed Density Update...is there one?

85_Ciera_Rebuild
03-20-2008, 06:56 PM
It was a Code 33 that I have all the time, in this post:

Mass Air Flow (MAF) Sensor (http://www.a-body.net/forums/showpost.php?p=2349&postcount=1)

and here is a post (http://www.a-body.net/forums/showpost.php?p=2472&postcount=6) of someone who gets a Code 34 with speed density software update.

85_Ciera_Rebuild
03-20-2008, 07:05 PM
Here is a post in another forum (http://www.turbobuick.com/forums/general-turbo-buick-tech/72831-speed-density-vs-mass-air-flow.html#post499621) that discusses vehicles that had MAFs, but they switched them to using MAPs

As noted, "Starting with Mass air on the 1985 TPI cars and going to Speed density in 1990. GM had a horrible time with the bosch mass air meters (same design as a GN)on those early TPI cars and it was most likely for this reason they switched. The main reason as I see it for the problems with the mass air meters failing was oil being spit out the intake on shut off contaminating the grid."

TheDeuce
03-20-2008, 08:24 PM
Let me check my 2.8 motor's code...I think it always has a Code 34, but that's because of speed density software....

Do not buy a MAF sensor...check again to see if you have a MAP sensor.

Also, look for a sticker on shock towers that says Speed Density Update...is there one?

I'm definately not buying anything until I'm absolutly sure that its bad. Money's been a bit tight for me for a while. I'll have to check later about the Speed Density Update. I'm done for the day working on it, after fighting to get the negative cable back on the stupid side pole battery.

TheDeuce
03-21-2008, 03:14 AM
I'll have to check later about the Speed Density Update.

Took a look under the hood, there was no notice about the Speed Density Update. So, I'm guessing I don't have it {?}.

85_Ciera_Rebuild
03-21-2008, 03:33 AM
Took a look under the hood, there was no notice about the Speed Density Update.

Unknown...it could have been done, but sticker could have come off.

Experiment - If you have a MAF on intake air plenum, unplug it, and see if you detect any driving/fuel differences....or codes being set right away, after starting.

My check engine light comes on all the time...but, if I can kept my foot on the fuel-peddle, it goes off....hence, if it works (engine), don't fix it, unless you live in a smog checking state:lol:

TheDeuce
03-21-2008, 04:15 AM
Unknown...it could have been done, but sticker could have come off.

Experiment - If you have a MAF on intake air plenum, unplug it, and see if you detect any driving/fuel differences....or codes being set right away, after starting.

My check engine light comes on all the time...but, if I can kept my foot on the fuel-peddle, it goes off....hence, if it works (engine), don't fix it, unless you live in a smog checking state:lol:

Yeah, I hear that. After all the fun with the negative cable, the 34 code or any for that matter come up, but its still acting the same- after coming to 180 degrees or so the oil pressure drops at idle to almost nothing as well as the revs and seems to want to stall after a time, and the oil pressure doesn't go up as high as its done for the last 4 years of me owning the car at start up, especially in this colder weather, and since the car runs at a little higher revs at start up in the cold to warm up the catalytic converter {the damn chilton's manual is pretty much all I've read fro the last week or so, can you tell?}

85_Ciera_Rebuild
03-21-2008, 05:27 AM
oil pressure

I highly suggest dropping the pan and installing a new oil pump.

Older 2.8 motors had a known problem of oil starvation....so either replace the oil pump soon, or start looking for another vehicle.

Pump is something like $40.00 or so...I re-used gasket

My Advice...do it, or unload it, and get another vehicle, if your oil pressure is at two bars or less at hot idle.

TheDeuce
03-21-2008, 02:04 PM
I highly suggest dropping the pan and installing a new oil pump...
My Advice...do it, or unload it, and get another vehicle, if your oil pressure is at two bars or less at hot idle.

This may be a stupid question, because I'm only slightly knowledgable about cars, but can the oil "thin" out? I do have oil pressure and it takes a long time for it to go down to 2 bars at hot idle, and that is only when I first come to a stop and the revs go way, way down and it seems like it could stall. Then it goes back up to 3 or 4 dashes depending on how long the car has been running. When I accelerate it goes back up to 40psi or so depending on the speed.

Also, when I first cleaned out the idle air valve a month or so ago I dumped fuel system/engine cleaner in there, could it have dumped a bunch of crap in the oil? I only have like 500-1000 miles left until I get an oil change and I've really only done city driving on the oil in there now with a few exceptions. Or could the idle air valve just be bad and throwing off the idle, which would affect the revs and engine speed or whatever?

Another thing, when my brake hose broke we had the car up on jack stands for a while and we ran it to bleed the new line. Could running it at that angle for a while make some sludge or debris or whatever get stuck in the filter thing in the pump? Right after we fixed the brake hose is when I started noticing this problem, but I hadn't driven the car for like 2 days before that because of a snow storm we got.

Like I said, money's a little tight and something like an oil pump replacement I would probably take to my local shop because, while I'm certain I probably could do it myself, the process of doing it in my driveway/garage would probably be too hard and frustrating, and I would be worried about screwing it up. Also, I'd hate to do that and find out after that there is still something up that could've been fixed cheaper and quicker.

Maybe I'm just in the denial stage of this whole problem.

85_Ciera_Rebuild
03-21-2008, 07:27 PM
2 bars at hot idle


My 2.8 has a computer controlled idle around 900 RPM, although I have seen it around 700 RPM....at what RPM is the question here, and is it a steady RPM.


goes back up to 40psi

With engine up to temperature, at some 50 degree OAT (outside air temp), I'm running that pressure around 40 mph...at 60 mph, I'm running around 50 psi plus range (8 bars).

Yes, 10 psi per 1,000 RPM is good if all engine parts are getting an equal slice of it.


some sludge or debris or whatever get stuck in the filter thing in the pump?


When I took my oil-pan off, there was sludge in the bottom, and I found the oil pump to be stuck in by-pass mode, which was the reason for low oil pressure.

Imho, buy an ACDelco PF52 oil filter, and before screwing it on, see if it will fit; on my vehicle, 88 Beretta, this oil filter just barely clears the cradle...when the engine rotates in forward or reverse gear. Secondly, buy 10w-40 or 15w-40 motor oil...its warm enough, where ever you live to use it, unless you really live in up North country.

85_Ciera_Rebuild
03-21-2008, 07:34 PM
..brake hose broke we had the car up on jack stands for a while....something like an oil pump replacement I would probably take to my local shop because...

On my 2.8, I had to:

1. Disconnect the battery
2. Remove the Starter
3. Remove the transmission dust cover
4. Remove the oil pan

Check the instructions for your vehicle (cite me an URL from this site for oil pump replacement (http://www.autozone.com/shopping/repairGuide.htm)), but it is not hard to do, imho...a little time involved, but if you had your vehicle up on Jack Stands, well, you can do it.

TheDeuce
03-21-2008, 07:51 PM
My 2.8 has a computer controlled idle around 900 RPM, although I have seen it around 700 RPM....at what RPM is the question here, and is it a steady RPM.

At temp, when the stuff starts happening, the revs go down to one or 2 dashes on the digital tach {this is when the OP goes down to 2 dashes} which I estimate to be 500 or less RPM. When I come to a complete stop and the sort of urge to not stall passes its at 3 or 4 dashs on the tach, which I would assume is about 500 {maybe?} or more rpm, and the OP guage usually goes up to 3 or 4 dashes, which I assume to be 15 or 20 PSI. {sorry if this is a little vague, I can't really go out and check it right now.



With engine up to temperature, at some 50 degree OAT (outside air temp), I'm running that pressure around 40 mph...at 60 mph, I'm running around 50 psi plus range (8 bars).

yes, mine 40 or so at 40, 45, 50 MPH. Like I said, I've mainly just done city driving in the last few months, and now with all this drama I'm a little leary of going on the highway, and then having something drastic happen and get screwed.


Secondly, buy 10w-40 or 15w-40 motor oil...its warm enough, where ever you live to use it, unless you really live in up North country.

I'm in Michigan, and right now its at freezing. We're supposed to get what they think might be the last snow today and tomorrow. I'm going to get the oil changed to either of those when I go get my tires rotated for free since they're due very shortly.

85_Ciera_Rebuild
03-22-2008, 04:22 AM
At temp, when the stuff starts happening, the revs go down to one or 2 dashes on the digital tach

Yes, yes.......now I've been there, done that before with my 2.8....the oil is too thin (or not enough is being sucked into oil pump), and your motor is hunting, and goes Kaput. It takes Horsepower to run the Oil Pump, and the computer program was setup as based upon specific parasitic engine drag parameters...but when the horsepower requirements are decreased, the motor assumes this fuel/air should do it, but it does not, so it goes up/down RPM.

Now Oil Lesson 101: See this chart

http://apps.volvocars.us/ownersdocs/1984/1984_DL_GL_and_Turbo/images/pg60a.jpg


When starting a motor with 10w-30, or with 10w-40, there is no difference, the viscosity is the same....10w is 10w, but when your motor is up to temperature, the 40w is a pinch thicker (higher viscosity) than the 30w.

Experiment - Buy 10w-40 oil (NOW) and one ACDelco PF52 oil filter (NOW), and change the oil/filter this weekend, when it is real cold outside:eek5: And report back Monday with your findings.

PS: Talk is cheap....action speaks louder than words...Do It.

TheDeuce
03-23-2008, 05:30 PM
So, I got the oil changed to the thicker stuff yesterday. No go on the filter, the guy looked it up on the AC Delco fit list and my STE wasn't on it. The deisel model was, but not the 2.8 V6 or the 4 banger. It runs slightly higher, about 2 dashes, but once it heats up its back down to 3 dashs at stops, it just takes longer to get there. Only saw it go down to 2 for a moment a couple of times, but it never sits at 2. It goes back up a moment after I come to a stop.

Since its Easter today I'll be seeing my sister's boyfriend, who does some mechanical work, and my cousin's fiancee, who rally races his subaru. Get some new eyes and ears on the problem.

CieraSL92
03-23-2008, 05:34 PM
So you changed the oil but not the filter?!

TheDeuce
03-23-2008, 06:57 PM
So you changed the oil but not the filter?!

Yes I changed the filter, it just wasn't the PF52 mentioned here.

85_Ciera_Rebuild
03-24-2008, 04:31 AM
...oil changed to the thicker stuff...2.8 V6...slightly higher, about 2 dashes...3 dashs at stops..

Oil pressure is related to actual oil temperature and engine temperature; ideally, to measure oil pressure you would have a pressure gauge and an oil temperature gauge. When your oil temperature drops, your pressure will rise a pinch....and cold air currents on your oil pan will affect your oil's temperature.

On my 1988 Beretta 2.8 V6 (167,000 actual miles), with 10w-40 oil fresh today, with engine up to temperature on 50 degree day.

1. Idle - 3 to 4 bars (700-900 RPM)
2. 1600 RPM (31 MPH) - 8 bars (50psi)

I may or may not see 9 bars (around 60 psi) with road speeds (45 mph + or 2200 RPM Plus); I need to drive it over a distance like 30 plus miles to see where it ends up, but I suspect my bypass is kicking in when oil is up to temperature. In any event, I've seen 8 bars and 9 bars....and will have to drive some more to see where it ends up at...just a pinch cooler oil temperature could take it up to 9 Bars...so with a sustain load on it (highway driving), I can determine if it will stay at 8 or 9 bars.

Filter - What is your current filter? If your earlier 2.8 uses the same stock filter as my 1988 2.8, then yes, a ACDelco PF52 might fit, if there are no cleance issues. Forget about what cross reference books say....check to see if a 1988 Beretta 2.8 uses the same filter as your 2.8...if true, the the PF52 will screw on OK.

85_Ciera_Rebuild
03-25-2008, 06:56 PM
it just wasn't the PF52 mentioned here.

Check to see if your stock filter is same as used on 1988 Beretta...again, if true, then if you have the clearance, the PF52 will work. It's always good to have a larger filter, especially when cost difference is peanuts.

10w-40 Experiment - I will be changing back to 10w-30, but my vehicle with engine up to temperature has similar idle and highway oil pressure readings...10w-40 does have higher pressure at lower R.P.M., but I think the by-pass is kicking in at 8 Bars (50 p.s.i.), so there is no gain in pressure with engine up to temperature at higher engine R.P.M.s.

On my digital dash, if you look at the alternator's normal bar level, it stays at eight bars like highway oil pressure...so, my gut feeling is that 8 bars was normal when vehicle was new. With 10w-40, it will hit 8 bars sooner than 10w-30 when engine r.p.m. is increasing, but this is not needed in my engine since I have enough pressure with 10w-30.

Imho, if yours is running at 2 bars at idle (700 RPM in Gear) with 10w-40, you need to yank out that Oil Pump, and get a new one...2 bars is about 6-12 psi, and this is where I made the decision to replace mine....Its a little time consuming, but a consumer can do it. Cite me an URL on how to do it, and I'll give an opinion before this is attempted.

85_Ciera_Rebuild
03-29-2008, 07:15 PM
Maybe I'm just in the denial stage of this whole problem.

Well, think about consequences of Sludge:

Toyota Oil Sludge
(http://www.autosafety.org/article.php?scid=150&did=566)



Sludge Warranties offered by Car Manufacturers (http://www.dontbuyone.com/)

Chrysler - (owned by Mercedes) says owners are a fault, offers nothing
Mercedes - 10 years unlimited miles, but nothing for Chrysler/Jeep/Dodge owners
Toyota - paying cost of sludge-related repairs for 3.3 million Toyota & Lexus owners.
Saab - extending engine warranty for 132,000 SAAB owners to 8 years, unlimited miles.
Audi - extending engine warranty for 1.8LT Engine owners 1997 - 2004, 8 years unlimited miles.
VW - extending engine warranty 1998-2004 Passant owners, 8 years unlimited miles


Taking that pan off, one can learn alot....my 2.8 had sludge in bottom of pan...not any more:wtf:

TheDeuce
03-31-2008, 04:44 AM
I'm trying to rule out everything else before I have to pull off the pan. The thing is the car only has 75,000 miles on it. I bought it like 5 years ago and it only had 40 or 50 thou. on it. It was an old lady's car, and she took meticulous care of it: every service interval it went in, oil changes on schedule, every thing done to it recorded and every reciept saved. I've changed the oil around every 4000 miles or so, never really beat it up and the furthest I've really taken it was up north one weekend to vist my cousin at school. As before, maybe just denial and apprehention to tearing the pan off.

Like I said, there is no knocking, grinding, or squealing or any sign that the pump isn't working or isn't working up to par or that the engine is suffering. I've been trying for a week to get the EGR valve off because my sister's boyfriend had a similar problem{lower and uneven revs and low oil pressure at warm idle} and it was a dirty EGR for him, but one bolt on it is a bitch and I can't get it off{another reason I'm leary about messing with the pan- I can't even get 2 bolts off the top of the engine without trouble, so I know I'll have trouble galore messing with the pan}. I pulled a muscle in my arm the other day so that hindered progress on it, as well as another snow fall. Hopefully tomorrow I can finally get the damn thing off. Also, what is the size of the bolts on the EGR on an '85 6000 with the 2.8 MFI V6? I know I have to replace the bolt now since I tore the head up. Even if it isn't the problem, I don't see any harm in cleaning it all up anyway.

But I am wondering about the possible vacuum leak. I noticed that when I turn the car off I hear a whistle/whine from the blower vent. I read something {possibly on a post on the website here} about pushing the vent button when the car is off and if you hear a sound then there is vacuum or something like that.

85_Ciera_Rebuild
03-31-2008, 05:40 AM
It was an old lady's car...40 or 50 thou. on it.

Oh no...from sludge city...never got warmed up before she turned the key off...etc...etc.

If most of her miles were short ones...then more sludge in the pan.

Read the directions for taking the pan off first....if no big deal...do it....or see what a mechanic charges.


possible vacuum leak....istle/whine from the blower vent.

This is a restricted flow....I would have doubts about it affecting engine....but you could plug the vacuum line to ducts and see...it comes off the intake manifold somewhere...pull it, and plug it...its that simple, if you can find a plug:werd:

EGR - When I looked at mine, it looked like an involved process....I'll look again, but I thought there was something screw-ball about taking it off.

85_Ciera_Rebuild
03-31-2008, 05:49 AM
replace the bolt now since I tore the head up.


Before taking out a bolt on aluminum, take a center punch and place it in center of bolt head, then with a hammer, give center-punch a moderate blow, then remove bolt. Also, use 6 point sockets....only 6 point, if bolt is a hex.