1995 bonneville - stalls and windows fail

[cmgarza]

I understand I know this forum started years ago, but thank you so much for the quick responce... I told the shop once again about the windows making the car stall and of course, im not a mechanic so there is just no possible way i can know anything.. theyre theory was just that the fuel pump was bad, just under 40 psi, so bad fuel pump, 600$ to install new one, and hasta la vista, basically.. but the problem continued as soon as i left the shop. so i dont think it was the fuel pump at all. i think it was the bad ground caused it to shut down, and more than likely it is still good.
see the thing is that i called n had to pay for a tow so they can fix the problem, they said they did a diagnostic check and said it was the fuel pump, then when i asked to see it, there wasnt one, he just knew it was the fuel pump because it was under 40 psi wen he did the pressure check. anyhow, since he didnt fix the problem and i paid him 600$ i dont want him to re-charge me for actually fixing it this time. thats why i asked about the fuel pump, if it is necessarily bad just because something caused it to shut down.
anyhow, thanks for the quick response.

[maxwedge]

Originally Posted by rkvons

If you have a marginal ground on your fuel pump and you make it worse by lowering your window (dumping more current to a bad ground), then your fuel pump will slow down/shut off. That does not mean your fuel pump is bad. Your old fuel pump was probably okay, but you just need to make sure the ground issue is fixed. The good news is, a correct repair can be verified by trying to roll down your window while the car is running and seeing that the fuel pressure remains high.

Correct, but it is possible a 18 year old pump could have been bad, but either way the shop misdiagnosed the problem and they should work with him, this is a 1.0 repair if you know what you are doing.

[cmgarza]

No..no..no, I just had the last fuel pump put in about 16 months ago.. before this one.. the mechanic I had before, thought I needed a fuel pump so he changed it n car still didn't start it ended up being the crank sensor, so that's y this time I actually sent it to the shop.. the fuel pump they just replaced wasn't old.. that's where my ? Pertaining to wondering if it was any good still came from....

[Tech II]

Hate to say this, but if you did not touch the power window, and the car started ok, accelerated from a dead stop ok, and would cruise at 55 mph, and then you lay into it and it took off, chances are the pump was ok.....


A ground should only have like, 0.10 volts drop across it.....if the car is charging at 13.0 volts, you will have close to that 13.0 volts across that pump. less a few tenths for the ground and the electrical connections in the circuit to the pump......

However a bad ground, can create a huge voltage drop, meaning less voltage to run the pump.....it would be interesting if you had a voltmeter across that pump with the car running......compare the voltage when not using the window and when using the window.......if there is a significant difference, you know that was your problem....now fix the ground......then do a comparison of the voltages again.......

[cmgarza]

so i told the shop i sent my car too, about the ground wires, and instead he replaces the fuel pump relay. The car was fine for 3 days, drove it, and raised the windows with no problem, until yesterday I was about to go out of town and before I got to the end of my street, tried to lower the window a little and again, the car stalled, right in the middle of traffic. So I got it pushed back, looked myself for the ground wires, found them and the metal plate that they are all connected to is corroded (green, white, black) My questions are can it be cleaned? would i have to cut all the wires (i dont want to mix them up)? The guy from the shop is going to look at it again. I hope he dont think he will be charging me anymore money. When Ive told them before what to look for. If they don't do it, I want to know if I can clean it or buy one from the dealer???

[rkvons]

If you have found the bad ground point, the problem is nearly solved. Depending on how thick the metal plate is, you can disconnect the wire that is attached to it and then take a wire brush attachment for a drill and buff the metal so that it is shiny and new looking. Then you strip the wire, or wires, that were connected there back and stick them in a thing like what is shown, solder them in and then drill a hole into the ground point (a solid metal point ) and stick a sheet metal screw in there and crank it down. Then take some grease and coat the hole area. This will be good for a few years. If that ground point is not good enough, choose another. You may need to get some large gauge wire to take you over to it, but the process is the same. Make sure that you do not drill into anything important.

[cmgarza]

well im not sure if its the bad ground point. all the wires look good, tightly soldered and the plate is thin, not thick..but the whole plate is corroded. i tried scraping some off, but what i was wondering if cleaning it would be better than trying to get that part from a dealer, i know it would be cheaper, but to get into the small area where the wires go with a brush will be kinda hard. unless the plate comes out, do you know if that medal plate comes out.? Im sorry just dont have much money, and know knowledge of cars.. i dont want to do it wrong, by mixing any wires up, by removing them..

[maxwedge]

You should cut out that soldered splice in the harness clean up the grounds in the splice and resolder all and use shrink tube and some way to seal up the junction.

[cmgarza]

Ok so the mechanic from this shop.came to get the car said they think it might b a bad fuel pump the put in and the ground wires don't have anything to do with this..I told them over n over about the grounds, its plain to c its all corroded, how is the fuel pump going to cause the windows n locks to make the car stall.. its clear that's its electric.. Idk, I paid way topmuch for a FUEL PUMP they said costed them $350 wen its only $72.99 at auto zone so I know they gtta probbley have a contract to get parts cheap.. I contacted the bbb hopin they can help me either fix the problem I paid already for, or give me some of my money back so I can go somewhere else. Period. If I wanted bullshit guesses I would've went to someone on the streets wit barely any tools.

[Tech II]

Well, it's painfully obvious, if you replace a fuel pump, and a relay, and the
EXACT same symptom, is there, it didn't fix the problem.....

WHAT KIND OF GARAGE IS THIS? It obviously was not a GM shop, or a high end chain.....If it was a GM shop, shame on them....

You told them about a possible ground problem....which they seemed to poo-poo.....

Ok so the mechanic from this shop.came to get the car said they think it might b a bad fuel pump the put in and the ground wires don't have anything to do with this..

I have access to a '96 manual....in it, G202 is the ground for the master power window switch....G202 is also the ground for the fuel pump......a ground problem here could potentially cause your problem.....G202 is located behind the kick panel in the E-brake area....

Complaining to BBB might not get your money back, but if this shop gets enough complaints from BBB, changes will have to be made if they want to stay in business....

[rkvons]

I don't know how anyone in their right mind would think that if you try to roll your window down and your fuel pump stops, that it is a bad fuel pump. I would think the conclusion would be that the window motor was bad. Sorry.

[Jrs3800]

we have seen a lot of these issues with the H bodies... More than most of the time its due to the ground buses getting wet and corroded... There are ground buses on both sides of the car, drivers side ahead and to the left of the seat under the carpet, and on the passenger side ahead of the seat and to the right under the carpet... These Ground Buses are the grounds for a series of different items, if they get wet and corroded they will cause a battery of problems, windows quitting are a dead give away... Clean those grounds, most likely that will be the solution...

[Tech II]

More than likely, they have been corroded by a water leak....when you remove that door sill trim, and lift up the carpet, you might be surprised how wet it is under there.....because of the rubber backing on the carpet, it will only seep through if the leak is real bad.....otherwise, the jute backing just gets soaked and corrdes the grounds.....

Can't tell you the numbers of SDM's and harnesses to the SDM's that I have replaced due to this.....GM had it on the floor under the PS seat....later the relocated it to the hump in the middle...

When you find water under there, you basically have to remove the interior of the car to get the carpet out to dry.....then wet down the car to find and repair the leak(body seams and water deflectors in doors seem to be the main culprits)......and then this is the time to check all those grounds that are exposed, and any harness connections, before reinstalling the carpet.......

[Nunziob]

I just wanted to thank everyone for their input. I just started having this problem with the car stalling when I simply touch the window switch. My mechanic friend had already figured that it was a ground problem and now we know exactly what the problem is--other than me buying this 20 year old car. It was interesting to read about your problem with a 9-year old car just 12 years ago. I have a 97 model. I really admire and appreciate all of you that know your way around these cars.

[Nunziob]

Originally Posted by 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

Thanks for all of the good info. I just bought a 97 model and started to have the same problem after my friend had worked on it for a month in his spare time.
This is going to save him some time.