98 GS - starts but won't run

[mboyd22]

My 98 GS starts and runs about two seconds then stalls. It does it totally consistently at all temperatures.

I've done an ODB scan and its not giving me any error codes.

Any one have any ideas? It will take about a week and half to go through the whole list of diagnostics ;-)

Thanks.

[mboyd22]

I found the answer to this problem in another post. It is the fuel pump resister. This problem is specific to the supercharged engine. The non-supercharged engine does not have this resister.

The shop manual shows it in the wiring diagram and it has a diagram that show the location, but there is nothing that describes how to diagnose it. An OBD-2 scan provides no indication of it.

It is located on the right front frame rail, just behind the bumper. Its buried in behind the windshield washer fluid tank. It would be a project to remove it, but fortunately its not necessary to remove it (see below).

When I went to the Pontiac dealer to get the part, I talked with a tech to ask him what the spec resistance is, and he didn't know, but said if it starts, runs 2 seconds and then dies, that's what it is.
He informed me that there was a technical bulletin on this as they changed the location the resister mounts. The new one has a much longer cable and it mounts on the firewall. Complete instructions are included.

To get to the plug to unplug the old one and plug in the new one, remove the front headlamp unit. This is easy.. just two clips that hold in place and one electrical plug in the back and out it comes.

The part was $46 from the Pontiac dealer. They are always cheaper than the Buick dealer across the street.

[agelder]

Could be the pump itself too. Has the pump been whining loudly lately?

[mboyd22]

The pump has been whining for the past year or so. Replacing the fuel pump resister fixed the problem as far as running.
Are you suggesting that the pump is failing and that caused the resister to fail?

If that's the case, then I will likely be replacing the resister again.
However, I haven't notices the fuel pump whine since I replaced the resister. I do notice that right after the car starts, the idle goes up to 1100 RMP which it did not do previously. I accounted for that as being higher fuel pressure causing a faster idle.

[buickregalSC97]

i having the same problem and i check it out at darsy motor thay told me it was my fuel pump and reg. i changed both properly and it saying i have no gas and i do and start, runs 2 sec and dies out how would i check if my resister is gone

[mboyd22]

I'm not positive where the resister is located on a 97, but I would guess in a very similar location as I describe in my previous post regarding my 98.

If you have a volt-ohm meter, you can check the resistence of the resister. I'm not sure what the resistence should be, but I would guess pretty small like about 10 ohms. Mine was 20,000 ohms which is essentially an open circuit - would pass no current to the fuel pump.

You need to find the connector for the resister, unplug it and then check the resistence. The mechanic I spoke to said, "if its starts, runs two seconds and then quits, its the resister." Based on that, I bought a new and that fixed the problem. Not that the new one comes with instructions that show you where the old one is located.

Good luck!

[agelder]

The pump failing will probably not cause the resistor to fail, but a whining pump is a sign of a dying pump. My pump whined for about a year or so before finally konking out. Unfortunately, it died on my wife when she was three hours away on a trip (dont think I've heard the end of that). Get a walbro fuel pump (340M if I'm not mistaken), and look at Intense Performance's website for the instructions on how to change out just the fuel pump. No need to drop the tank, there's an access panel. It's a heck of a lot cheaper than the entire assembly from GM, and not that hard of a fix (did it in a wal-mart parking lot at 2am).

[Old Lar]

It could be the ignition resitor for that chip on the ignition key . That sounds like the same symptoms that I had on my 99. It had to be towed to the dealer for the fix $$$$.