I have a 88 iroc (305 tip auto). When cold the car starts and rpm drop to around 500 for a few seconds. For the few seconds the car runs rough and after it dies. I need to give it throttle to keep it alive. Once it’s warm and I drive it the the car once a to hesitate on acceleration and backfire. I have changed the Distributor, mass airflow sensor, idle air control, both mass airflow sensor relays, spark plugs and spark plug wires. Could it be the fuel pump or the fuel pump relay?

 

Any error codes for cts ?

 

No error codes for the cts. The cts has been replaced by the previous owner.

 

What’s fuel pressure? Might have to datalog or use a scanner to see what’s going on during warmup.