98 stalling on ride home from work o. its not the FP relay.

[chriskirbyh2o]

hey guys, I'm just going to post my problem search through the forums. Car runs fine. Then random stutter and the car shuts off.all lights remain on. I sit on the side of the road for a minute and then restart the car.I just purchased a new fuel pump relay and the problem is still there.I have posted this problem before and everyone thinks is the ICM, thee camshaft or crankshaft sensor, or the connectors to the ICM. the only new information I have is that the problem went away for about 3 months then just came back today. Let me know what you think

[Bonny77]

I have on 2004 Bonn, 6cyl SE similar intermittent problem, seems to run fine for a while, and on highway. Then (not all the time) it starts hesitating at idle (stop sign or stop light). Step on gas to pull out and it acts like it is not getting enough fuel, rough "roooom, roooom" almost dying, then it pulls out like no problem. I changed the Idle Sensor, cleaned throttle body, Mass Air and throttle position sensors but problem still "comes and goes". When it starts acting up, I noticed a “humming” sound like the fuel pump when you turn on the ignition switch to ON, and the voltage gauge drops below 12V with the sound as it starts hesitating. Step on gas to rev-up RPM and as the voltage goes back up, the sound goes away. Could the fuel pump be going bad?

[Wes]

I would check the ICM first as others have recommended to you. If you remove it, it can be tested at most chain parts stores. Just a word of caution though, these tests are known to have their flaws. Sometimes bad ones will test good though so take it with a grain of salt. But, usually if they test bad, they actually are. They should already know to, but if they test it once, and move on, ask them to try it 3-5 times. Not more though as you can over heat, and kill a perfectly good part.

[MKMike]

I have on 2004 Bonn, 6cyl SE similar intermittent problem, seems to run fine for a while, and on highway. Then (not all the time) it starts hesitating at idle (stop sign or stop light). Step on gas to pull out and it acts like it is not getting enough fuel, rough "roooom, roooom" almost dying, then it pulls out like no problem. I changed the Idle Sensor, cleaned throttle body, Mass Air and throttle position sensors but problem still "comes and goes". When it starts acting up, I noticed a “humming” sound like the fuel pump when you turn on the ignition switch to ON, and the voltage gauge drops below 12V with the sound as it starts hesitating. Step on gas to rev-up RPM and as the voltage goes back up, the sound goes away. Could the fuel pump be going bad?

When my fuel pump was failing in my 93, that's exactly how it started to run, then it started stalling when letting off the gas.

The voltage drop and humming may be due to the pump drawing excessive amperage.

Rather than just tossing parts in, you can check fuel pressure and amperage draw which will often pinpoint the culprit.
If the pressure is low, make sure the fuel is going through a clean fuel filter, as a dirty filter will cause problems.

Here are a couple of good articles with fuel pump troubleshooting info:
http://www.popularmechanics.com/cars/ho ... ce/1272391
http://www.carid.com/images/airtex/fuel ... series.pdf

[chriskirbyh2o]

Thanks for the replies. I'm on the side of the highway right now checking replies while I wait for my car to start. I'm going to start looking for a fuel filter/pump to buy I suppose since my mechanic friend also said he heard a humming from the rear.

[chriskirbyh2o]

Well the trannie is starting to slip, shifts hard after it gets warm, and the temps are rising here in SD so the stalling problem is returning with a vengeance and I am looking for a new car. I want to keep it and fix it up a lil. I was reading some threads about trannies and was wondering what to do about a failing torque converter clutch?