I have a 91’ firebird that stalls about 5 seconds after I start it. If I keep trying to start it about 5 or 6 times the car kicks over and then runs fine . I get codes 23 and 54 would that mean the M/C solenoid is bad or what? It only really started doing this after I put a cleaner into the gas tank.

Thanks for any help

read the post ive had going for a few months now, having same problem, but cant get it to stay started peroid,

Try an injector leakdown test.

EDIT: Might also want to check your fuel pump relay. If it's bad, the pump won't turn on until adequate pressure is built up and sensed by the oil pressure switch.