Having a strange problem with this car, only has 50K original miles on it too. No check engine light either.

Lately..especially when it is cool (a.m.) and then when it is hot and I have the AC on. The car is not wanting to start, idle, or will die. I will describe things in order in case they are different issues.

First observation.
In the a.m. I go to turn over the car and I hear the fuel pump prime and then crank a few seconds...acts like it is going to start then doesn't. I do this a few times..I never depress the gas pedal during this time. Then if I put my foot on the gas while cranking the car will start up and run...but then when I let off of the gas..it will idle really rough and will stay that way...UNTIL I turn the ignition off and pull the key out, reinsert it the key....then re-start the car...then it fires right up and idles fine.

Second observation.
Similar to the first but now it is hot out temps 90-105*, I turn the AC on and it will hunt and die after it starts. If I take the key out and re-start it will fire up and run perfect.

Third observation.
After sitting over night, I will start the car and fires and runs perfect..but no matter if it is this way or what I described in the "First Observation" it always billows some white/grey smoke when it starts the first time...never any other time...only after it has been sitting. It doesn't smell like fuel either.

I don't think it is coolant as I am not losing any..could it be valve seals?

So what is the problem?

 

TTT hoping somebody will chime in with experience.

 

OK I will keep chiming in since I have replaced a couple of motors and assembled long blocks in my time on Chevy, Mopar, and Ford. I just have been in the LSx world for so long now that coming back to the archaic sensor PCM system of the TPI..leaves me depending on those experts that have remained in the field.

So the car has been starting perfectly the past couple of mornings and afternoons. I will check the fuel injectors, but was also wondering if it could be some sort of temperature sensor.

Does anybody know if a temp sensor is used for the ECM to determine what AF mixture is needed at start up?

Thanks