Chevrolet Repair: Hard to start hot, fuel pressure regulator, sensor mat

Question
I have a 90chevy bretta 3.1lt after you drive the can and it gets hot then shut if off you are unable to restart it for about 1hr or untill it cools.  After you get restarted it has a problem at the 2500-3000rpm range where it is very sluggey.  The following items have beed replaced to repair other problems that I have had with the car in the six months. ECM, coils, spark plug and wires, fuel filter, MAP sensor, throttle sensor, MAT sensor,and idel air control motor.  Also the TCC plug was disconnected because I had a problem downshifting when I came to a stop. The only thing that I could think next was a fuel problem, but I am not sure.

Answer
Next time the vehicle will not start when it is HOT, try spraying a little starting fluid in the air cleaner and see if it TRIES to start better. It will NOT start and run constantly, But what we are looking for is if it does seem to want to start easier.

You could have a fault with the IAC motor as just because it is NEW does not guarantee that it is working properly.


You may also have a fuel pump problem that is HEAT SENSITIVE and does not like to pump efficiently when it is HOT or you could have a fuel pressure regulator problem or sometype of an ignition problem.


You need to determine if you do NOT have ignition to the spark plugs or the fuel injectors or no fuel to the injectors BEFORE we can do any more diagnostics.