I've got the same problem recently started on my daughter's 99 Grand Am. The car turns over and fires strong most every start. But three times in the last two weeks, it has turned over but refuses to fire. All three times were after it was driven or warmed up. After a while, the car starts strong again.
The first time it happened, she was at a friends apartment and I was sure she ran out of gas, even though she told me she had just put gas in it. The gauge is broke so you have to work off mileage rather than reading the gauge. Anyway, I picked her up and figured I look at it the next day. Next day, went to look at it and it started like nothing ever happened.
Didn't do anything with it (exept think about how that could be) and a couple days later, she got stranded in a small town about a half hour from our house. Since I was thinking fuel or spark earlier, I decided to pick up some plugs on the way out to get her. I replaced the front three (easy ones), and she fired right up. So now I pretty comfortable that it must have been the plugs, figured I'd do the other three at home. Had her follow me to the gas station to make sure it had gas, and it wouldn't start back up again. Changed the other three plugs at the station, and fiddled around with a few other things, but couldn't get it to fire. I gave up on it and left it at the station.
Went back the next day with my toolbox, but didn't need them because the damn thing started right up. So, figuring this had to be a deal where it would not start when the car was warm, I drove it back home, picked up a driver to get my Jeep back from the station, and drove it back home again. Total drive time about 2 hours. Now I'm figuring when I do finally stop it, it won't start. Wrong, it started up perfectly fine. Started up again the next morning with temps in the teens. And when I say started up, I am talking with no hesitation at all.
So, I'm still scratching my head, and today I started it and let it warm up at idle. Shut it down and tried to start it and it won't start.
The only thing I can find that makes any sense is a loss in fuel pressure, but I'm thinking that if that were the case, the car would sputter a bit while driving which is not the case. Once it is started, it runs really well. So.......anybody have any thoughts or experience with this?
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