1989 Cadillac Brougham Stall Problem

[George Woodford clc21025]

I have a problem with my 1989 Cadillac Brougham with 24K miles.

The problem:  After I drive the 1989, 5.0 L for a short period (engine warmed-up) and while applying the brake just before coming to a stop, the engine wants to stall or stalls in the case I push the brake pedal too far.  Usually, I start to release the brake some so it does not stall.  There are no trouble codes stored in the computer.  I had the carburetor rebuilt, which resolved a problem with the TPS, apparently an unrelated separate problem.  I'm checking the condition of the Manifold Distribution Presure Sensor that is mounted on the fender well inside the engine compartment.  It appears to me that there is a vacuum problem that is causing this stubble condition while breaking just before coming to a complete stop.  What about the Power Break Booster? A bad booster or valve on the booster itself? Transmission problem? Any ideas? Thanks...

[John Paul]

Unplug your case connector on the trans. check eng light will come on, but the stalling might stop for you. if that works for you it's an easy fix.. replace the lock up sol...

[35-709]

Not that J.P. needs it, but I agree with his take on the problem.

[John Paul]

Not that J.P. needs it, but I agree with his take on the problem.

I often find I need all the help I can get Geoff  If I left somthing out, let me know.. I just want to help out on the board.. I have meet alot of real good solid people here.. and I don't want to scare the good ones off...

[The Tassie Devil(le)]

I thought the Stall Speed of the Standard Torque Converter was around 1,800 RPM.

Bruce.

[Guidematic]

If you are also experiencing a shuddering, and if the car lugs around corners and from slow speeds, I would say that JP is correct here.

This is a common problem with the THM 2004R transmission, the lockup convertor does not disengage before the car comes to s top, and stalls the engine. Replacing the TCC solenoid will resolve the problem. It's not a difficult job, and only requires removing the trans pan to access. It's also a good excuse to change the fluid and filter.

But verify first that this is the issue.

Mike

[TJ Hopland]

Are you 100% sure the choke is working properly?  That is the #1 problem I saw on the 307's. which leads to the #2 issue of plugged cat converters.

What was the carb issue?

[Guidematic]

BTW, I forgot to add, the manifold distribution thing you speak of is the manifold absolute pressure (MAP) sensor which senses manifold vacuum, to help the ECM determine engine load. If there was a problem there, it would almost certainly set a DTC.

Mike

[George Woodford clc21025]

I ordered a GM part TCC and should have it this week; this discontinued original part is becoming more difficult to find and will make a good spare if it is not the problem.  I'll report any findings later.  In reference to carburetor, I was getting a High Voltage TPS code.  This is no longer the case the last time I ran the car after the carburetor rebuild.  Thanks for all the input. 

[George Woodford clc21025]

The TCC is fine.  I didn't have to replace it.  I did disconnect the converter and the problem became more pronounced.  Reconnected the converter.  The transmission representative feels it is not the transmission.  Interesting problem with sympthoms very very similar to what happens when the converter is disconnected.  I have to replace the alternator; it is failing with lamp glowing on the dash.  Any other clues to what this problem might be?

[Rusty Shepherd CLC 6397]

  The transmission representative feels it is not the transmission. 

I had a strong feeling that it was not your transmission.  Although stalling as you come to a stop is the usual symptom of torque converter clutch trouble, you said that if you let up on the brake pedal as you come to a stop it doesn't stall.  If it were the TCC, it would stall as your speed decreased to a stop or near stop regardless of what you were doing with the brake pedal, and since the power brakes work off of engine vacuum and releasing pressure on the pedal would lessen the vacuum draw, I wonder if you might have a vacuum problem.

[John Paul]

Rusty you may be right.. I find it is impossable to fix someones car from a keyboard.. All we can do is tell you what we think.. I'm kind of puzzled that the problem was worse with the cas connector off.. I've never experanced that before..

[Glen]

I am puzzled about this conversation because my 89 shop manual indicates this is a fuel injected engine.  But George says he had the carburetor rebuilt. 

Unless someone retro fitted a carb on it; it should still have the fuel injection system on it.

With that in mind I would suggest checking the ISC (idle speed control).  When those things go bad they get sticky and can cause stalling when the throttle is closed. 

Just my 2 cents. 

Glen

[Guidematic]

I am puzzled about this conversation because my 89 shop manual indicates this is a fuel injected engine.  But George says he had the carburetor rebuilt. 

Unless someone retro fitted a carb on it; it should still have the fuel injection system on it.

With that in mind I would suggest checking the ISC (idle speed control).  When those things go bad they get sticky and can cause stalling when the throttle is closed. 

Just my 2 cents. 

Glen

Then you have the wrong shop manual. All 1989 Broughams were built with the 307 Olds with a Carb. There is a specific shop manual for these cars.

Mike

[TJ Hopland]

Yep all 89's were carbs.  I believe that 90 had the optional towing package with a TBI chevy that then became standard in 91.   It was the same drive line that was in the Olds Custom Cruiser wagon and the Lesabre Estate wagon (if they still made it that year).  Those cars went to the round body in 91 and the EFI motors.  The Brougham and Wagons had very few changes through the 80's.  Even the radios and door handles did not change like the rest of the line. 

Since the problem happens with the brakes is it possible that booster is leaking and its the vacuum leak that is causing the stall? 

[Glen]

Then you have the wrong shop manual. All 1989 Broughams were built with the 307 Olds with a Carb. There is a specific shop manual for these cars.

Mike

OK, my bad.  My manual is a De ville/Fleetwood manual. 
It is surprising to me they had a carb in ’89.  Does it have a ECM? 

Glen

[Guidematic]

Yes, it has a feedback carb. There is an ECM that controls the spark curve and the duty cycle of the mixture control solenoid in the carb. It also controls other functions like EGR, cannister purge and so forth.

This system is known as Computor Command Control, or CCC or 3C.

Mike

[Glen]

Thanks for the education.  I did not mean to hijack the thread.  Sorry for the detour.  I hope you guys can help George fix his problem. 

Glen

[George Woodford clc21025]

I have solved the problem! I contacted Abel Automotive Service, www.carburetorsrus.com, 410-288-9400, in nearby Baltimore, MD who rebuilt the carburetor.  Wayne suggested that I check the operation of the EGR Valve and especially the EGR Solenoid.  The Valve tested okay.  I checked the EGR Solenoid at the source input vacuum port and noticed it was always open.  So, just before stopping the car, the port should close and it wasn't closing.  Purchased a new EGR Solenoid Assembly and replaced it.  The problem was solved.  The engine on this car is loaded with valves and solenoids.  A few years ago, I was failing the emissions test due to a failed Vacuum Regulator Valve.  The valves and solenoids for this car/engine are GM discontinued, and are becoming difficult to find.   

[KelleyCpSpares]

I have the very same problem you had (see my thread at http://forums.cadillaclasalleclub.org/index.php?topic=121962.0) but as my thread shows I plugged off the vacuum to the EGR valve in an attempted to isolate the problem BEFORE bearing the expense of another automotive part purchase and in doing so DID NOT solve my problem. So as you can see I'm certain the EGR Control Solenoid 3-Pack cannot be MY problem. Are YOU absolutely certain that replacing it fixed YOUR problem, or did it simply go away for a time only to return?