Mechanics

CUTS OFF WHILE GOING DOWN THE ROAD

1996 Pontiac Bonneville

I have a 96 bonneville that keeps cutting off going down the road, but it is just not cutting off in one session. It will start up and run fine for a day or so than just cut off and not want to start back up. But after a bit it does. The fuel line; fuelI have a 96 bonneville that keeps cutting off going down the road, but it is just not cutting off in one session. It will start up and run fine for a day or so than just cut off and not want to start back up. But after a bit it does.

A brand new engine along with a load of sensors and modules were put in it a year 1/2 ago, it has not been run much, just started.

Runs fine when it does start and goes, engine sounds great, no sign of over heating, new termostat put in it a month ago; fans work.

It is like something is over heating and when it cools off the car will start and run but will cut off another time which could be at any time or a day later.
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Maureen
April 11, 2012.




Get the fuel pressure checked. It sounds like a fuel pump.

Roy

ASEMaster6371
Apr 11, 2012.
A new fuel pump was just put on. I have had a new fuel pump; fuel line; fuel filter; that thingie inside the gas tank cleaned or replaced (forget which) a new ignition module put on. I'm sure some other things but would have to go look at the receipts.

Tiny
Maureen
Apr 11, 2012.
Going to need to start from scratch with a compression test, fuel pump pressure check, even though it is new, and spark test. One of them is failing and need to find out which one is failing.

Roy

ASEMaster6371
Apr 11, 2012.
What is a spark test? I know when the mechanic put it on the computer nothing registered. They are stumped by it. Could it be a sensor and if so any ideas which one. I do appreciate you taking the time to help with your advice. I just do not understand how it could start up; run great; and then all of a sudden cut off while going down the road. I have noticed that when it does it, I have just been at a stop and am picking up speed or taking a turn.

Tiny
Maureen
Apr 11, 2012.
That test is best left to a good tech as it could hurt you if you tried it.
It sounds like you need a better shop to help you here.

Roy

ASEMaster6371
Apr 11, 2012.
Oh is that the test where they take off one of the covers on the spark plug and see if it is getting current? They did that and yes it would hurt or at least it looked like it stung the mechanic when they did something like that at the shop, It was a pretty blue though, lol.

Tiny
Maureen
Apr 11, 2012.
Ok, then the actual pressure test for the fuel pump. This is done with a gauge.

Roy
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ASEMaster6371
Apr 11, 2012.
Had the same problem, it was a bad ground. Do you notice anything else not working when it stalls. Pwr windows, fuel pump?

Tiny
Hilman
Apr 18, 2012.
What do you mean a bad ground? Where would that be coming from and what needs to be looked at or corrected? Well I did have an issue where when I used the power windows and seat adjustors it would cut the car off. They said that they may have been caused by moisture build up from the water that collected during the rain.

They have blown out the gas line that feeds back into the tank to make sure that a vapor lock isn't occuring and causing it to shut off when everything heats up and I guess builds up. Still haven't gotten it back so I do not know if that did anything but would love hear more about this bad ground thing and how to fix it.

Tiny
Maureen
Apr 18, 2012.
Do a search on "1999 Pontiac Bonneville fuel pump problem with 105000 miles". This should bring you to the dialog that another person had with my same problem that helped me fix mine. It has a good picture of the splice pack that the ground wires go into and explains where to find it.

Tiny
Hilman
Apr 18, 2012.

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