1995 bonneville - stalls and windows fail

[cscottyr]

Hello Everyone,

Well my problem isn't a new one. My bonny - will stall at about anytime and anywhere - and yes various power ckts will also fail at the same time. I have cleaned every power connection that I can find. Today I was hoping to get some replies with similar problems - Several threads here have listed answers to this problem - One guy rebuilt his starter - another person found the problem in some wiring on the drivers side of the car in some shorted wiring. Some ignition modules and or coils have been replaced (do these drop out the power rail when they fail????) Interestingly enough I did not find any threads that indicated that cleaning power connections fixed the problem - Also, no one indicated that replacing their alternator fixed the problem. One guy did replace a battery with a leaky cell - he also replaced a neutral saftey switch. I dont know which of those actions actually solved his problem. Since so many people have had a stalling problem and a power accessory problem at the same time (especially on 1994 and 95 models)- I thought it would be a good place to start a sort of clearinghouse where a collection of potential repairs could be cataloged. So if you have had a stalling and power accessory problem at the same time -What did you fix to make it better. Anyone out there want to comment???

thanks cscottyr

[randman1]

Originally Posted by cscottyr

- and yes various power ckts will also fail at the same time.

Specifically what circuits are failing at the same time? My first thought is a ground problem as there are only a small handfull of ground points on these cars. If one were to become intermittent or faulty, it could interrupt a whole host of circuits. If your other failing devices share the same ground point, i.e. PCM ground is located under the ignition module, then this would be the most likely cause

[cscottyr]

Hey randman1,

Thanks for the input. Door locks and pwr windows are the two accessories that have failed with the system - I wasn't aware of the ground under the the ignition module until earlier today - I was going to look at that very soon.
Thanks again for the reply!
cscottyr

[jkinney]

cscottyr, I had to do some intense troubleshooting on my 94 SSEi, but due to slightly different reasons. Only because on mine, the volt light would come on shortly before It started dieing. The way I started diagnosing was I purchased an ACTRON scantool and hooked it up, and drove around, days on end (and not too far from my home). The obvious symptom I found was the volts would slowly start decreasing (on the scantool "battery" catagory) from 14.3 at startup, to 9 volts then it would die. My GM service manuals for the car stated the PCM will power down at 9 volts. Long story short, this was with a new battery and a new replacement alternator (105 amp,...not good enough for these cars). My problem ended up being tarnished "power" connectors damn near everywhere, Power Distribution under the hood, fuse blocks, and main connector under the dash on the drivers side. One of them fixed it, just dont know exactly which? Didnt hurt to clean all of them though. When I get a chance this weekend, I'll look and see what the service manuals recommend for your problem (sorry, but tight schedule). Good luck.

[cscottyr]

Thanks jkinney for the post!

[cscottyr]

Well I found something new to think about - with the ignition on the resistance between my positive and negative rail drops to around 500 ohms - lower than it should be - Therfore - I am begining to think that I should check everything that picks up when the ignition turns on. I'll keep looking.
cscottyr

[cbushnell]

I am having the same problem, relatively speaking. My wife's 96 Bonneville has been stalling lately. It all began with problems starting (fuel pump not turning on). I noticed that when it wouldn't start, the windows and door locks wouldn't work either. I started driving the car to see if i could duplicate the problem. Well, last friday on my way to work I tried to roll down the drivers side window and the car quit. I coasted to a stop, called my wife to have her drive me into work, and figured I'd worry about it later. After work I fought with it. After a 45 minute battle it started (as near as I can figure holding down the power window switch did it) so I drove it home. When I got home, as a test I tried to roll down the driver side window again. Once again it stalled. I have read what has been written about the alternator and battery, but don't believe that is my problem. The guage is reading the high side of normal (acceptable) and the battery is good. But the symptoms are identical to the ones you have been listing. I looked at the "pigtail" to the fuse box under the hood and cleaned the connection there. This did not fix it, so I ran another wire (just in case the wire was bad) and still had no luck. My car has not been able to start since I got it home, no matter what I try, and I am completely at a loss. My wife and I both love the car and don't want to get rid of it. Does anyone have any other suggestions?

[cscottyr]

cbushnell,

I wish that I could tell you that I have it all under control and have fugured it out- unfortunately that is not the case. I sidelined my bonny mid summer to work on the house - Fortunately I had another car that I could drive. I was planning on getting back into it very soon however since the weather is turning cold quick. I have really wanted to check out the starter solenoid for some time. I dont have the schematic but am relatively sure it picks up with the ignition switch. You are lucky that your problem is always broken. If you check your positive power rail - you should see voltage lower than 9vdc. If you start disconnecting one thing after another eventually you should come to the offending ckt. Your battery could be shorting out also. - Take it to the zone and get a load test done on it. It sounds like your alternator is sound - but your battery is still in question (lso turn your lights on and see if your battery will support that.
Please let us know if you get an answer - I plan on starting to work on mine again in two weeks.
God Bless!
cscottyr

[cbushnell]

I have an appointment at a garage today, and last night rather than tow the car (just because I'm cheap :-) I tried to start it and it started... It actually started! I was able to start the car by holding down the power window button until the window actually started to go down. As soon as it did I let off and hit the key, it started right up. So, I drove it to the garage, or tried to rather. About 1/4 mile from the garage I passed under the shadow of a tree, and because it is so helpful, my car turned its own headlights on. As soon as the headlights turned on the car quit. I am convinced that it is quiting because the voltage gets too low (but my guage was still reading right around 13). I am wondering if this might be caused by a bad connection on the starter (I assume the alternator charges the battery back through the starter connection ? ) Anyhow, I will be giving all of the helpful information I have gathered here to my mechanic in hopes of it helping him and cutting down on the diagnosis time. As soon as hear his findings I will post them in hopes of it helping all the rest of you.

[cscottyr]

cbushnell

Thanks for update!

cscottyr

[cbushnell]

The garage called on thursday and told me the car needs a new fuel pump. I explained (for the 3rd) time to the mechanic that the car quits when accessories are used, but he refused to "hear". I told him to go ahead and replace it since the gas tank leaks a little and the sending unit lines are iffy (and if those are getting done, might as well do the pump too). Anyhow, I don't see where that will solve the problem unless the fuel pump is causing the short. Any thoughts before I pay this guy 600 to not fix my problem?

[cscottyr]

Hey cbushnell,

Tough question. A failed fuel pump is easy to diagnose - a pressure gauge at the fuel line and you could know very quickly. These pumps are notorious for failing - often around 80000 miles. As far as it causing your accessory voltage problem- not likely - but possible. If you are leaking around your fuel tank and have to pull it I would definitely look closely at your pump at that time - no sense in doing that job without replacing the part (knowing how often they fail). However, if I had a mechanic looking at my car - and he wasn't giving me the time of day - I would leave and go elsewhere. I think I would ask him why he thinks the fuel pump is bad - you may have more than one problem - Good luck - I wish I could offer you more help.

[cbushnell]

The garage called me back yesterday afternoon. The GM dealer sent the wrong fuel pump and sending unit. He contacted the dealer and they said the right parts would be an extra $200, for a grand total of somewhere around 850 to change the tank, sending unit, and fuel pump. I told him not to bother. It looks like I'll be doing the work myself, bu it should only cost around 400 in parts. Then, once that is done and it is still stalling on me, I can take it in again and ask that the stalling problem be diagnosed again. I'm really beginning to wonder if it is worth the hassle.

[mhollon]

Originally Posted by cbushnell

The garage called me back yesterday afternoon. The GM dealer sent the wrong fuel pump and sending unit. He contacted the dealer and they said the right parts would be an extra $200, for a grand total of somewhere around 850 to change the tank, sending unit, and fuel pump. I told him not to bother. It looks like I'll be doing the work myself, bu it should only cost around 400 in parts. Then, once that is done and it is still stalling on me, I can take it in again and ask that the stalling problem be diagnosed again. I'm really beginning to wonder if it is worth the hassle.

That's most likely NOT what's wrong with your car! I went thru the same thing last year, pump and all, they still hadn't fixed it....turns out, it was a shorted ground wire in the driver's side footwell area that was causing it to die. NOT the fuel pump I paid to have replaced! Seems the Driver's door seal had been leaking into the footwell area and had saturated a ground wire, the GM Tech found it, Spliced a new wire in and that took care of it! You are having the EXACT same symptoms I was. Everytime I would try to roll down a window or hit the Power Locks the inside lights would go out and something would make a funny crackling noise. But it would leave me dead.

Hope this helps!

MarkH
Ohio

[cscottyr]

Hey cbushnell,

Sorry about all the heartache your going through. I wouldn't pay that kind of money fo that job either. Autozone hase your sender and fuel pump for around $250.00 - you'll need a filter - maybe some lines and a tool to diconect your filter. I would buy new tank straps also. It's really not that hard of a job especially if your tank is near empty or you have a drain plug. However - before you go through all that - I would purchase a pressure gauge (aprox - $25.00) and do the following.

Turn the ignition ON; the fuel pump should run for a few seconds. Check the pump pressure for the following specifications:
1.

1987-93 vehicles, except 1993 VIN K: 41-47 psi (284-323 kPa).
2.

1993 VIN K and 1996-99 vehicles: 48-33 psi (333-376 kPa).
4.

Start the engine and allow it to idle. The fuel pressure should drop about 3-10 psi (21-69 kPa) due to the lower manifold pressure.

I tool this off the auto zone websight. Good luck - let me know how it turns out.

cscottyr