fuel pump or sensor??

I have 98 regal gs w/ supercharger bout 130,000 miles.Car will start and run for like 5 sec then cut off if i keep my foot on the gas it stays runnin till u let up and then dies.had someone tell me its the fuel pump but the car shouldnt even start if the pump was bad right??

had someone tell me its the fuel pump but the car shouldnt even start if the pump was bad right?? Nobody can tell you if your fuel pump is bad without checking the fuel pressure! :shakehead Normally, the engine requires 35 psi to start and maintain rpm and 42-47 psig is normal. Is this problem only evident when the engine is cold, or all the time?

Based on the symptoms you have a classic bad fuel pump resistor. Try the relay bypass at the following link below. Relays are marked differently on a Regal but the same principle applies.

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=658282)

Let me know if you need any further info including a parts source.

cant find a local parts store w/ the resistor is this a dealer only part besides ordering off internet?
thanks for the input!!

GM dealer only item or at the link below:

Click here (http://www.pfyc.com/pc/WB3006/GPUNDER/Official+GM+Fuel+Pump+Resistor+Kit.html)

GM Part Number: 88951182, MSRP $48.39

Also, www.rockauto.com and www.gmpartsdirect.com should have it.

I too have a '98 Buick Regal with a similar past but still having issues:

Originally exhibited the same symptoms as described (starts fine but dies shortly thereafter)
- car towed to mechanic, they replaced fuel pump, fuel filter and crank sensor (reading this thread makes me doubt that the pump was really bad :( billed about $850)
- drove about 30 miles and died again with the same symptoms
- car towed back to same mechanic and they replaced resistor ($250)
- drove for about 250 miles and died again with the same symptoms
- car towed to different mechanic and they came to the conclusion that it was the resistor ($125)
- after telling them that it had just been replaced, they shrugged their shoulders and gave me the one they had replaced
- I ohmed out the "bad" resistor and it measured the same as the "good"
- I replaced the "good" resistor with the recently "bad" and car started and ran fine

What is going on? :banghead: Is there something in the troubleshooting process of testing for the resistor that is clearing some other malfunction (no check engine light)? I'm afraid to count on the car until I find out what is going on. Any help is appreciated.

Ken

I too have a '98 Buick Regal with a similar past but still having issues:

Originally exhibited the same symptoms as described (starts fine but dies shortly thereafter)
- car towed to mechanic, they replaced fuel pump, fuel filter and crank sensor (reading this thread makes me doubt that the pump was really bad :( billed about $850)
- drove about 30 miles and died again with the same symptoms
- car towed back to same mechanic and they replaced resistor ($250)
- drove for about 250 miles and died again with the same symptoms
- car towed to different mechanic and they came to the conclusion that it was the resistor ($125)
- after telling them that it had just been replaced, they shrugged their shoulders and gave me the one they had replaced
- I ohmed out the "bad" resistor and it measured the same as the "good"
- I replaced the "good" resistor with the recently "bad" and car started and ran fine

What is going on? :banghead: Is there something in the troubleshooting process of testing for the resistor that is clearing some other malfunction (no check engine light)? I'm afraid to count on the car until I find out what is going on. Any help is appreciated.

Ken

Welcome to AF.

What exactly are your symptoms? A bad fuel pump resistor exhibits a unique pattern of failure but your problem may be elsewhere.

I don't think it is the resistor either based on both "good" and "bad" resistors having the same impedance and operating the same when the car is "working".

As far as specific symptoms:
The vehicle starts perfectly, and then 2-3 seconds later dies. If I keep reving the engine (i.e. about 3000 rpm), it will keep running but if I let the rpm drop, it dies. No matter how long it runs (by me reving the engine) or how many times I go through it (I've counted well over 50 before), it always turns around and starts perfectly. Each time I've had it in the shop, the "process of troubleshooting" has seemed to temporarily "fix" the issue as I truly don't believe that specifically replacing the resistor had anything to do with the change (my opinion, not that of a professional).

I hope this helps explain better what is going on.

Thanks,
Ken

I don't think it is the resistor either based on both "good" and "bad" resistors having the same impedance and operating the same when the car is "working".

As far as specific symptoms:
The vehicle starts perfectly, and then 2-3 seconds later dies. If I keep reving the engine (i.e. about 3000 rpm), it will keep running but if I let the rpm drop, it dies. No matter how long it runs (by me reving the engine) or how many times I go through it (I've counted well over 50 before), it always turns around and starts perfectly. Each time I've had it in the shop, the "process of troubleshooting" has seemed to temporarily "fix" the issue as I truly don't believe that specifically replacing the resistor had anything to do with the change (my opinion, not that of a professional).

I hope this helps explain better what is going on.

Thanks,
Ken

I see the typical fuel supply components like fuel pump, filter and resistor parts have been replaced but was the fuel pressure ever tested at the front fuel injector rail to see if it is actually in specs to totally rule out a fuel supply issue? Were the fuel pump and fuel pump speed control relays checked?

Also based on your symptoms try disconnecting the MAF sensor and see what it does. With ignition to off remove the electrical connector to the MAF sensor located on the top of the throttle body and then start the engine. Idle may be a little erratic until engine warms up sufficiently.

i had a 1999 olds intrigue with the same problem ----replaced the fuel pump car started and died--its was my air mass flow sensor 3800 eng computer did not have a code-

Had similar problem in a cutlass 3100 started fine but cut off unless u gave it gas. I cleaned the idle air valve and inside where it sits and it never cut off again . Just giving insight good luck

Update - issue found (late in posting, sorry): It turned out to be an intermittent connector that hooks up to the resistor. It looked like some corrosion on the connector as well as some heating of the wire (discoloration and slight deformation of insulation where it is routed by the radiator and had a gap in the wire wrap where it exits from the main harness). I could hold the wire/connector one way and the engine would die. I'd wiggle it a little, and it would start running again. I replaced the connector and about 12" of wire and routed it away from the radiator. About $20 for the connector at the local shop and problem is fixed.

Thanks for all of the help,
Ken