Grand am won't start when warm

[Tibb79]

I have a 95 grand am that will start when cold and run fine, but if you either turn it off after it's warmed up or let it idle (runs gradually rougher then dies after about 10 min), it wont re-start for about an hour. Any ideas?

[xeroinfinity]

Welcome to Af Tibb79.
May hav a pluged fuel filter, amoung other things.
Is this a 4 or 6 cylinder?
A dirty air filter can also do this.
Your egr could be pluged or bad.
Bad grounds on the starter or engine, check the battery terminals too.
Any other syptoms, or things you knowticed when this occured?

[Ridenour]

Another possibility would be a dying fuel pump - they experience thermal shutdown when they're going bad.

[Tibb79]

Fuel, air filter are new. I went for the easy fixes first. Is there any way to test the other things while engine is hot?

[xeroinfinity]

well the fuel pump can be checked with a pressure gauge, check it cold, then check it when the engines warmed up to see if theirs a drop in pressure.
The egr can be taken off to see if theirs carbon built up in side preventing it from working.
As the grounds go, you'll just hav to look around the engine to see where they are connected to the body and if theyare loose.

[silverado122775]

I had the same exact problem in my Silverado. when it's cold, start's fine.. after it warms up.. has a hard time starting. You need to replace the Fuel Preasure regulator. Part is about $60-100. I replaced it myself.. not sure where it is located on the grandam.. should be near the intake manifold along the fuel line.

[Tibb79]

Forgot to mention one other symptom. The oil level light stays on and I checked the oil, it is fine. If you let the car warm up and then shut it off then quickly restart it, the light goes off. Damn I hate this car.

[xeroinfinity]

maybe your conection plug on the oil level sensor is loose or dirty, not letting it always make contact anyways. ITs underneeth the car, on the bottm of the oil pan. They get really dirty down under their.

Dont think that would make the car not start when it gets warmed up.

[atorres61]

Originally Posted by Tibb79

I have a 95 grand am that will start when cold and run fine, but if you either turn it off after it's warmed up or let it idle (runs gradually rougher then dies after about 10 min), it wont re-start for about an hour. Any ideas?

I have a 1996 pontiac grand am that used to do that. I replaced the pickup coil. Have you done that?

[Tibb79]

No, I have'nt done the coil yet. Would that be temp sensitive?

[cokebeetle]

If it turns out not to be the fuel: the water coolant temp sensor (located near the thermostat) will seriously mess with the computer. Among other things it controls ignition advance curves (cold engine vs hot) and cold fuel enrichment. See http://www.wellsmfgcorp.com/counterp...erpoint2_2.pdf for details. I think the referance Ohm readings are low but it's good info. Pull the sensor and Ohm it out... go to the local auto store and see if they will let you Ohm/compare before you buy (and BTW it's cheap). If all else fails, its worth a try... and a lot easier than changing a fuel pump. Good luck.

[gmack221]

Another cheap try is the crank positon sensor, when they are getting ready to go out they will sometimes quit working when warm. But be ready to break the old one getting it out (they swell up in the block) (I assume you have a quad 4), and its easy to do if you pickup a new intake gasket and pull the intake, or you can fight with it, but I have big hands, so I usually pull the intake.