I am having a particular issue that I am hoping you guys can help me with. I recently changed the fuel pump and sender on the stock 2.8. The vehicle starts perfectly and runs perfectly for a while then it quits. I noticed that when the vehicle is cold, no issues are present but once the vehicle is up to temp and running for a bit, it will stop running and literally leave me on the side of the road. Once it cools down, it will fire up and run again and the cycle repeats itself. Besides changing the fuel pump and sender, nothing else has been changed on the engine. The gas on the tank is in good condition so no bad gas. Before changing the mentioned items, the vehicle was running perfectly and was extremely reliable. The fuel pump was changed as matter of precaution and the sender due to the fuel gauge not working. I would greatly love some input.
Before changing the mentioned items, the vehicle was running perfectly and was extremely reliable. The fuel pump was changed as matter of precaution...
No guarantee that the new fuel pump (and wiring/hose connections) are all good, or that you didn't goof at some point in the process. I agree that it's quite possibly the ignition module, but it's so easy to test the fuel pressure on a 2.8... so check it!
[This message has been edited by Patrick (edited 06-21-2021).]
I had this same problem on two Fieros that sat for several years. The gas tanks had rust on the inner surfaces, and some of the rust came off and settled into the bottom of the tank. The cars started and ran fine, but under power the sediment evidently gets sucked up to the filter sock and caused the engine to stall. I did a chemical restoration on the inside of the tank on one car, and the problem went away. I used the three step system of treating, sealing and coating the inside of the tank from KBS Coatings, but there are several companies that sell a kit.
Thank you all for the replies. ok, fuel pressure with old fuel pump prior to changing it was 35. Fuel pressure with new pump is the same and holds that pressure. When I replaced the pump and fuel sender, I verified the tank and there was no sediment at the bottom of the tank of any kind. I do have a new ignition module so I will change that and see what happens.
Thank you all for the replies. ok, fuel pressure with old fuel pump prior to changing it was 35. Fuel pressure with new pump is the same and holds that pressure. When I replaced the pump and fuel sender, I verified the tank and there was no sediment at the bottom of the tank of any kind. I do have a new ignition module so I will change that and see what happens.
Cool, then ignition module is most likely as the others suggested. Let us know the results!
Thank you all for the replies. ok, fuel pressure with old fuel pump prior to changing it was 35. Fuel pressure with new pump is the same and holds that pressure. When I replaced the pump and fuel sender, I verified the tank and there was no sediment at the bottom of the tank of any kind. I do have a new ignition module so I will change that and see what happens.
You should be up around 42 psi!!. Try another gauge. You can also pinch off the rubber portion of the fuel return line near the tank and retest. Vise grips with a piece of cardboard on the jaws to keep from damaging the hose. If you don't get 42 psi or better you have problem in tank. If no pulsator present the ONLY HOSE that will survive the ethanol is SAE J30R10. The interior as well as the exterior of this type hose is protected from ethanol. Dig deep in your wallet cause a foot of it will be worth the cost of a steak dinner.
Spoon
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
If no pulsator present the ONLY HOSE that will survive the ethanol is SAE J30R10. The interior as well as the exterior of this type hose is protected from ethanol. Dig deep in your wallet cause a foot of it will be worth the cost of a steak dinner.
The best price I could find when I needed it relatively recently was $16.70 (USD) at RockAuto for a foot of the stuff. (Only actually need about three inches.) Not a bad price compared to the ripoff prices charged by some vendors.
Sorry about the delayed responses. Family issues came up. I have changed the Cap and rotor as well as the ignition module. Car starts fine and runs stationary with no issues. Car warms up to operating temperature and at no point does it ever stall. The issue still is when driven for a while. Next steps, recheck the fuel pressure.
Sorry about the delayed responses. Family issues came up. I have changed the Cap and rotor as well as the ignition module. Car starts fine and runs stationary with no issues. Car warms up to operating temperature and at no point does it ever stall. The issue still is when driven for a while. Next steps, recheck the fuel pressure.
Logic says put the known working fuel pump back in and see if that takes care of it. If it does then you should return the new pump under warranty less sweat & labor and if you have to buy another one later on get it someplace else and a different brand just in case.
Your fuel pressure should be checked under real operating conditions versus in the driveway with engine idling or revving with no real engine load. Years ago I installed an electronic fuel pressure gauge on the 'A" pillar so I could monitor it any time by merely shifting my eyes to the left. To me it's as essential as a tachometer and removes all doubt & wonder. The fuel "pressure sensor" is on the fuel rail along with the injectors.
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
[This message has been edited by Spoon (edited 07-29-2021).]
OK. I replaced the coil and when I removed it, the top pin where the boot connects to fell off. I installed the new one and the car started fine. Went for a drive and 15 minutes into the drive the car sputtered and stalled. The more I gave it gas, the more it hesitated until it would stall. Every time I turned the ignition on, I could here the fuel pump come on but the car would not start. I waited about ten minutes and the car would turn on and drive for about 200 feet and then it would repeat what I said. Finally. had to have the car towed to my house. Back to square one. BTW, The spark plug wires, cap and rotor, coil, fuel pump, fuel sender and fuel filter are brand new. Suggestions, welcome!
Went for a drive and 15 minutes into the drive the car sputtered and stalled.
Well it certainly sounds like the ECM is not happy with an input from a sensor once engine is up to temp, and that it runs fine off the built-in tables until then.
Any ALDL engine codes saved?
[This message has been edited by fierosound (edited 08-02-2021).]
I have not checked but the check engine light come on initially upon start up and never again even when is not running correctly. I will check tomorrow and post the findings.
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Originally posted by fierosound:
Well it certainly sounds like the ECM is not happy with an input from a sensor once engine is up to temp, and that it runs fine off the built-in tables until then.
OK. I replaced the coil and when I removed it, the top pin where the boot connects to fell off... The spark plug wires, cap and rotor, coil, fuel pump, fuel sender and fuel filter are brand new. Suggestions, welcome!
I see no specific mention of a pickup coil.
When you just say "coil", we don't know if you're referring to the ignition coil or pickup coil.
Correct. Sorry about that. I meant to say ignition coil. Also, the spark plug and wires have been replaced as I am giving the car a well-needed tune-up. The car is running much better but at some point during the drive, if I give it more gas, it will start to hesitate and even backfire.
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Originally posted by Patrick:
I see no specific mention of a pickup coil.
When you just say "coil", we don't know if you're referring to the ignition coil or pickup coil.
From that I take it then that the very inexpensive pickup coil hasn't been replaced? If not, you should do it... especially considering you've already replaced many of the other ignition components.
Did you re-check your fuel pressure? As pointed out previously, 35 psi seems a little low.
You also need to check the readings from your MAT and CTS to make sure the ECM is being fed the actual temperatures.
I had this problem once. After about 10-15 minutes of driving the car would stall and restart after a ~10 min wait, where it would run for a similar short period. It turned out to be the distributor. Perhaps a problem with the magnet on the rotor spindle, or a clearance issue from wear and rust of the interrupters. Whatever the case, attempts to restore it failed and a new distributor solved the problem. I had a friend with a similar experience on a Nissan, with normal cold starts followed by a stall after operating temps were reached.
I will check the fuel pressure once I replace the ignition pick-up coil which will be here tomorrow. I will try to change it out this weekend if time allows. I did remove the rotor, cap, and ignition module. Two things stood out to me. One, the ignition pick-up coil wires were severely pinched by the cap (could be the cause of my troubles), and the shaft of the distributor, where the rotor sits, is rusty-looking. I don't know if that is common or not.
Alex
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Originally posted by Patrick:
From that I take it then that the very inexpensive pickup coil hasn't been replaced? If not, you should do it... especially considering you've already replaced many of the other ignition components.
Did you re-check your fuel pressure? As pointed out previously, 35 psi seems a little low.
You also need to check the readings from your MAT and CTS to make sure the ECM is being fed the actual temperatures.
