I can't figure out what it is.

The car starts fine in the morning, whenever it's been sitting for a long time (several hours) or if I just finished an hour long road trip, got out for a second, then got back in.

But, if I take the car for a short trip (like to the gas station), turn it off, then try to start it again, it just keeps rolling, but it won't fire up. You wait a couple hours, and it will fire up and run fine

There is nothing wrong with the starter, the fuel pump, the battery, or the computer, they're all new


argggggggggggggggggggggggggggggggggggghhhhhhhhhhhh hhhhhhhhhhhh

 

My 2001 Chevy S10 2.2L has the same problem! My battery is having issues, but even when it is hooked up to a charger it has problems. (yes my alternator is still good). I changed the starter too. I think I have a problem with the Air Injection system. I would like to hear more opinions.

 

You may have a leaky injector and the car gets flooded when you first turn the engine off. Next time it happens, try cranking the car with the gas pedal floored. This tells the computer you want to clear a flooded condition, and it turns off the injectors to clear the flood condition. Give it a try & see if it helps.

 

I was thinking the leaky injector like Pete said, or possibly an ignition module. I went through 3 of them on my 86. It would run for around an hour fine, but much more than that, and it died, and wouldn't start, nor would it start if I turned it off myself after driving for more than a few minutes and got right back in. Turned out the modules were overheating and wouldn't work untill they cooled down, and I ended up having to replace the distributor.

 

Giving it gas doesn't help me personally. I think it has something to do with the EGR valve or the Air Injection. When it fails to start, there is air coming out of the intake and same when it shuts off. This doesn't happen all the time, but it happens right before I have a hard time starting.

 

OK what would the symptoms be if the fuel pressure regulator was not working properly?

PS how does it work physically?

 

Well it's like valve. As the vacuum is applied the diaphram is opened that allows fuel to flow more.

 

Dead again, I am running out of ideas here
I've replaced about everything, help!!!!!!!!!!!!!!!1111

 

Please don't let this thread die, think real hard

thanks

 

You never said what car you are working with, but in general this is how it goes.
Are you getting a check engine lite?
Get a fuel injection pressure gage, about $25, and check the pressure at the fuel rail with the engine running( 40 PSI +- 5 PSI if you have port injection, around 15PSI with TB injection), then turn off engine & note if the pressure is dropping. The pressure should hold for several hours, if it drops rapidly there is either a leaky injector or a bad regulator. To test the regulator, with engine running disconnect vacuum hose to regulator, if good the fuel pressure will go up 4-10PSI.

Also check the coolant temp and intake air temp sensors, they could be giving false indications & confuse the PCM.