Engine starts when cold, but not after engine is warm and temp gauge is flat line

[raythecaddie]

This topic seems to be a common problem where an engine will start no problem when cold, but after it has run for a while and you shut it off you have a difficult time starting the engine again. The trouble starting the engine almost feels like a carburetor that is flooded.

Here are my combined issues that happened today...I first noticed that the tach was erratic, slightly surging at moments, I also noticed at the same time that my temp gauge was flat lined. I went into a store, when I came out the vehicle had a hard time starting, it felt flooded and I had to floor the gas pedal to get it to start, after it started I took my foot off the gas and the tach was holding steady at 3000rpm, and it took a few moments for it to go down to 1200rpm, where it stayed while idling.

Now I started googling this issue and there are so many suggestions of what it could be such as;

Crank position sensor
Coolant level sensor
Coolant temperature sensor
Cam sensor
Mass airflow sensor

Now based on all the combined issues that happened to me what would you narrow down the possibilities to???

Thanks in advance for your time to read this and your input, I appreciate it very much.

Ray

 

[Scottydoggs]

being you gave no info on what car, engine in it or even the year of said car. ill toss my 2 cents in with a guess. if its a na engine the fuel pressure regulator could be bad. its in the fuel rail, pull its vac line off sniff it, if you smell gas the fpr is bad.

 

[raythecaddie]

Sorry about the missing information, I have a 2006 Grand Prix 3.5L base model

 

[Scottydoggs]

i think you mean a 3.8 aka 3800

and i think 06 has the fpr in the gas tank. so thats not likely it.