PDA

View Full Version : This just hasn't been my year with this thing...More problems.



SexySilhouette
10-24-2012, 11:44 PM
After 6 years of mostly solid reliability, the van -1995 Olds Silhouette L27 3.8 - may be parked permanently...The transmission has been rebuilt, the A/C system has been completely replaced, new LIM, new plenum, new ICM, new brakes all the way around, new front hubs, new tires and more.

Lately I've been having a bad hesitation. I've put in new plugs, wires, coils, ICM, crank sensor, cam sensor, related wiring, done a compression test, fuel pressure test, checked it on TunerPro RT, and it's still there.

It also "pounds" at cruising speed. Like the TCC is stuck, It goes away if I tap the brake pedal or accelerate, but gets worse at deceleration.

Plus the A/C is still leaking, it takes about 2 weeks for it all to leak out. I've put dye in and nothing shows up. :uh:

So I guess I'll ask here before giving up.

Duke George V
10-25-2012, 12:23 AM
Have you cleaned the MAF recently? What kind of gas do you use?

85_Ciera_Rebuild
10-25-2012, 11:35 PM
bad hesitation...."pounds" at cruising speed.


Hook vacuum gauge up to a true intake vacuum....drive around, and notate vacuum readings at idle, light load, heavy load, and deacceleration.

Unplug brake booster's vacuum-line, and plug it off....here where stopped at home, check vacuum at idle, and at a higher RPM....then unplug brake booster's vacuum-line and plug it. Then recheck vacuum readings at idle and higher rpm. Also, drive it, but check to make sure you can stop it with your foot before going faster.

SexySilhouette
10-25-2012, 11:38 PM
Have you cleaned the MAF recently? What kind of gas do you use?

Yes...I run 89.

85_Ciera_Rebuild
10-25-2012, 11:41 PM
Intermittent Hesitation While Accelerating or While Cruising (http://www.aa1car.com/library/diagnose_buick_3800_engine.htm)

An intermittent chuggle or hesitation that can be felt during light acceleration or while cruising at highway speeds with no Check Engine light or no fault codes set may be caused by intermittent operation of the automatic transmission torque converter clutch (TCC). The problem is not the torque converter clutch or clutch solenoid, but a faulty input to the powertrain control module computer from the engine's throttle position (TPS) sensor. The fix for this problem is to replace the TPS sensor.

Vehicles that may be affected by this include the following:
1995-1999 Buick Riviera
1995-2004 Buick Regal
1995-2005 Buick LeSabre, Park Avenue
1997-2005 Buick Century
1995-2001 Chevrolet Lumina
1995-2002 Chevrolet Camaro
1995-2005 Chevrolet Monte Carlo
2000-2005 Chevrolet Impala
1995-1997 Oldsmobile Cutlass Supreme, Ninety Eight
1995-1999 Oldsmobile Eighty Eight
1998-2002 Oldsmobile Intrigue
1995-2002 Pontiac Firebird
1995-2003 Pontiac Grand Prix
1995-2005 Pontiac Bonneville
with 3800 V6 Engine (VIN K - RPO L36)

85_Ciera_Rebuild
10-26-2012, 12:23 AM
i've put in new ...



tps....yes?

SilentWing
10-26-2012, 12:41 AM
As far as the AC goes did you check your evaporator/evaporator drain to see if that's where it's leaking from? That's a common place to check if you can't find the dye...

SexySilhouette
10-26-2012, 01:20 AM
Intermittent Hesitation While Accelerating or While Cruising (http://www.aa1car.com/library/diagnose_buick_3800_engine.htm)

An intermittent chuggle or hesitation that can be felt during light acceleration or while cruising at highway speeds with no Check Engine light or no fault codes set may be caused by intermittent operation of the automatic transmission torque converter clutch (TCC). The problem is not the torque converter clutch or clutch solenoid, but a faulty input to the powertrain control module computer from the engine's throttle position (TPS) sensor. The fix for this problem is to replace the TPS sensor.

Vehicles that may be affected by this include the following:
1995-1999 Buick Riviera
1995-2004 Buick Regal
1995-2005 Buick LeSabre, Park Avenue
1997-2005 Buick Century
1995-2001 Chevrolet Lumina
1995-2002 Chevrolet Camaro
1995-2005 Chevrolet Monte Carlo
2000-2005 Chevrolet Impala
1995-1997 Oldsmobile Cutlass Supreme, Ninety Eight
1995-1999 Oldsmobile Eighty Eight
1998-2002 Oldsmobile Intrigue
1995-2002 Pontiac Firebird
1995-2003 Pontiac Grand Prix
1995-2005 Pontiac Bonneville
with 3800 V6 Engine (VIN K - RPO L36)


tps....yes?

Mine is a VIN L Series I 3.8 but yes, that was the first thing I checked and it tested fine.


As far as the AC goes did you check your evaporator/evaporator drain to see if that's where it's leaking from? That's a common place to check if you can't find the dye...

I did and nothing there.

85_Ciera_Rebuild
10-26-2012, 02:32 AM
Mine is a VIN L Series I 3.8 but yes, that was the first thing I checked and it tested fine.



Well replace it....

For a transmission shop that has Snap-On tester, they could do a check ride, and see what's happening.

Duke George V
10-26-2012, 05:27 AM
Yes...I run 89.
Octane doesn't really factor in to it. If you're running unbranded stuff from the local Gas 'N Go or whatever, it's probably clogging up your injectors. Chevron and Shell have really good detergent additives. You could also throw a "21 gallon" bottle of Techron into the tank next time you fill up (before you put gas in). How about your fuel filter?

85_Ciera_Rebuild
10-26-2012, 11:43 AM
Mine is a VIN L Series I 3.8...

Info U get on internet is not complete....I would buy a new TPS, and install it.

Also, have you disconnected battery for say 24 hours? Assuming your ECM dumps datapoints.

85_Ciera_Rebuild
10-26-2012, 11:55 AM
Like the TCC is stuck, It goes away if I tap the brake pedal or accelerate

In this diagram located here (http://www.smokemup.com/tech/700r4.php), I would disconnect wire going to TCC solenoid, if this is the case for your vehicle...I don't know how ECM in your vehicle gets signal to turn off TCC solenoid, so look at vehicle's wiring diagram.
http://www.smokemup.com/gallery/pictures/other/700wired.gif

SexySilhouette
10-26-2012, 08:40 PM
Octane doesn't really factor in to it. If you're running unbranded stuff from the local Gas 'N Go or whatever, it's probably clogging up your injectors. Chevron and Shell have really good detergent additives. You could also throw a "21 gallon" bottle of Techron into the tank next time you fill up (before you put gas in). How about your fuel filter?

Ah, I run Valero usually. Chevron if I'm around there. Just changed the filter 2 weeks ago.

SexySilhouette
11-02-2012, 09:05 PM
New TPS and it is just as bad. Anyone else?

85_Ciera_Rebuild
11-02-2012, 11:04 PM
New TPS and it is just as bad. Anyone else?

Brake Switch...are there dual wires there? One for brake lights, and one to let transmission know to kick out lockup torque converter?

Disconnect or Connect it, which ever it is...so transmission does not engage lockup.

Duke George V
11-02-2012, 11:39 PM
Can you still unhook the TCC wiring harness from the transmission on the 4T60E? That was the band-aid on the 440T4 and TH125 when lockup was acting up.

85_Ciera_Rebuild
11-04-2012, 10:26 AM
1995 Olds Silhouette L27 3.8


Could a salvage yard ECM be tried?

Again, dis-engage lockup TCC, and try it.

85_Ciera_Rebuild
11-04-2012, 05:55 PM
bad hesitation...."pounds" at cruising speed. Like the TCC is stuck, It goes away if I tap the brake pedal or accelerate, but gets worse at deceleration.

I can trouble shoot better when I learn about all parts within a system...OBD II ECMs, I know nothing specific.

That said, after thinking more on this topic...I suspect there is a vacuum sensor (MAP, etc) that triggers shifting into lockup mode....see if there is a vaccum sensor that triggers lockup TCC...check the specs and test it.

Hence, what is complete circuit that controls TCC...brake switch, vacuum sensor, TPS....understand that circuit.

85_Ciera_Rebuild
11-11-2012, 01:42 AM
Update...??? MAP ???

Ray_McAvoy
11-11-2012, 02:14 AM
This is from the 1995 U-body GM factory service manual and might be helpful for troubleshooting:


TCC Operation
For the torque converter clutch to apply two conditions must be met:
- Internal transaxle fluid temperature must be correct.
- The PCM grounds switches internally to turn "ON" solenoids in the transaxle. This moves check balls, which will allow the torque converter clutch to apply, if the hydraulic pressure is correct as described above. The TCC "APPLY" solenoid controls the flow of transmission fluid to the TCC. The TCC Pulse Width Modulated (PWM) solenoid varies the hydraulic pressure at the converter clutch regulator valve to make locking and unlocking of the TCC smoother.

The PCM controls the TCC apply and PWM solenoids after looking at several parameters:
- Vehicle Speed Sensor (VSS). Speed must be above certain value before the clutch can apply.
- Engine Coolant Temperature (ECT) Sensor. Engine must be warmed up before clutch can apply.
- Throttle Position (TP) Sensor. After the converter clutch applies, the PCM uses the information from the TP sensor to release the clutch when the vehicle is accelerating or decelerating at a certain rate.
- A TCC brake switch which opens a 12 volt signal to the PCM when the brake pedal is depressed.


As 85_Ciera_Rebuild suggested earlier, I'd recommend taking a look at that TCC brake switch. And if that checks out okay, it might be worth checking the wiring for any loose or intermittent connections to the TP sensor, that TCC brake switch, and to the transaxle.


Can you still unhook the TCC wiring harness from the transmission on the 4T60E? That was the band-aid on the 440T4 and TH125 when lockup was acting up.

I don't think that will work with the 4T60E because that plug/harness contains more than just the TCC wiring. It also contains wiring for the shift solenoids.

SexySilhouette
01-23-2013, 03:29 AM
Sorry for not updating sooner. New wires and it's been fine ever since. Driven it all over and no problems. Even the A/C seems to be holding a charge - had to use it today.

Prospeeder
01-23-2013, 04:23 AM
on the A/C line orings you oiled them right? When you say replaced everything, whats that mean. Evaporators, condensors, rubber lines can all leak. Add dye to the system and the leak will be found eventually. if you see the dye on the drain for the Evaporator housing then you know its the evaporator.

SexySilhouette
01-24-2013, 12:33 AM
on the A/C line orings you oiled them right? When you say replaced everything, whats that mean. Evaporators, condensors, rubber lines can all leak. Add dye to the system and the leak will be found eventually. if you see the dye on the drain for the Evaporator housing then you know its the evaporator.

Yes I did. And I did add Dye, never a trace. Even checked the Evap and nothing. I couldn't find the leak.

Jr's3800
02-19-2013, 12:05 PM
What kind of plugs and wires did you use the last time they were done? Hope its still running good..

babyivan
02-19-2013, 05:49 PM
Sorry for not updating sooner. New wires and it's been fine ever since. Driven it all over and no problems.
I had the same problem on my former 3800 Regal.
For me, it was because I bought the cheap wires from Autozone (Duracrap). After putting on a set of Acdelco wires, I had no more issues.

Also, be sure that you re-use the spark plug boot heat shields, I know of a lot of people that simply threw them away thinking they were not needed or just part of the oem wires.

Even though there's less heat up front, having them on the front plugs is a good idea too!
My current 3.8 has them up front, but my Regal didn't, so I had to order 3 of them.

85_Ciera_Rebuild
02-21-2013, 01:42 AM
I bought the cheap wires from Autozone (Duracrap).

Always check OEM's mm and match it. That said...

Bosch Opti-layer Mag (http://www.boschautoparts.com/wiresets/pages/sparkplugwiresets.aspx) Technology - Bosch provides premium quality, pre-assembled spark plug wire sets for virtually all American, Asian, and European cars, vans, and light truck applications. And all Bosch Premium Wire Sets are backed by a "no hassle" lifetime guarantee.

Spark Plugs and Spark Plug Wires Cross Reference Guide (http://sears.pammar.net/sparkplugapp.pdf)

85_Ciera_Rebuild
02-21-2013, 02:28 AM
cheap wires from Autozone (Duracrap).


I was reading in foreign car forum tonight that there has been a change in spark plugs and wiring used.

As noted there, "the correct combination (http://www.peachparts.com/shopforum/vintage-mercedes/271436-bosch-spark-plugs-wr7dc-vs-w7dc.html) would be low resistance wires and resistor plugs ,the standard norm now .

vintage was standard ignition wires and resistance end caps to keep ignition chatter down.

Resistance wires and resistance plugs would pull down performance and starting issues may arise."

Also,]


There has been a lot of discussion on this subject in the past! Many opinions. But in end, it seems to me:
- if you have OE style wires with built in resistors, then use non resistor plugs.
- if you have new style Bosch wires without resistors, then use resistor plugs.