Well, my N* fiero is acting up. It seams to not want to start up every couple days. It turns over fine and starts to fire like its getting air and spark but then dies like its not getting fuel. When it does start, which is most of the time, it runs fine. Any one have experience with this? My first thought is maybe the fuel pump is going bad or I have a bad ground or something. My brother thinks it might be b/c the computer is reading low oil pressure and cutting the fuel. I'm not sure about that though b/c the guage reads good pressure....
You really can't diagnose without doing a thorough scan of the pcm. This may not be the answer that you were looking for but there is no way around it. Either you keep guessing or do it the way the pros do.
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When it happens try flooring the gas and cranking to see if it then starts. If it then starts but starts by running rough and then clears out look for a leaking injector.
When you first turn the key on do you hear the fuel pump run for two seconds? Bump the starter - does the fuel pump come on again for two seconds. It should for both. Then start the engine and turn it off after 10 seconds. Does the fuel pump run for a while even with the engine off?
Finally get this to happen again and then listen for the fuel pump. Is it running when this problem occurs?
You are going to check this with a fuel pressure gauge instead of just replacing the FPR right?
Yes it could be the FPR. It could be many other things also. Guessing parts, replacing them and then seeing if the problem still exists is a frustrating, slow and expensive way to solve problems.
Auto or stick? (not relevant, just curious) Have you watched a fuel pressure gauge while it's experiencing the problem?
Stainless or nylon fuel rail?
It's an auto (4T80). The fuel pressure gauge is next. Based off what I learned on the Cadillac forums it is most likely the Fuel Pressure Regulator or the fuel pump. Based on the sporadic nature though, its looking more like the FPR and that appears to be a common problem on the N* when it goes over 80K miles, which mine recently did. Fortunately, its a cheap part which I am going to replace regardless of what the fuel pressure gauge says just to be safe...
It could also be your IAC unit on your throttle body.
Make sure it has a clean seat and pintle head from carbon deposits. Doesn't hurt to put a new one in place or to have a back up for its future failing.
It's an auto (4T80). The fuel pressure gauge is next. Based off what I learned on the Cadillac forums it is most likely the Fuel Pressure Regulator or the fuel pump. Based on the sporadic nature though, its looking more like the FPR and that appears to be a common problem on the N* when it goes over 80K miles, which mine recently did. Fortunately, its a cheap part which I am going to replace regardless of what the fuel pressure gauge says just to be safe...
Good. Step through the troubleshooting tree and be patient. Throwing parts at it without a solid diagnosis is a waste of money.
Also, the Fiero tends to end up with a very warm fuel tank after extended drive times. Old fuel pumps don't like that and can allow the pressure to sag on a restart.
