1989 Corvette starting and idle problems

Replace the coolant temp sensor, not the coolant temp sending unit

My 89 corvette is hard to start when it is cold, and runs very rough for about a minute. replaced the IAC and Maf sensors had the throttle body cleaned, now it idles very high and emits the same problems. i also had the injectors cleaned.

I HAVE THE SAME PROBLEM AND TURNED MY IDLE ADJ SCREW DOWN BUT THE IDLE STILL GETS STUCK I ABOUT 900 RPMS AND I HAVE TO TAP THE GAS PEDDLE DOWN TO GET THE IDLE TO DROP TO 600 CAR IN DRIVE AT A STOP I THINK I HAVE TO CLEAN OUT MY IAC BUT I AM NOT SURE THIS THIS HAPPENNED AFTER I CHANGED MY BAD INJECTORS I RESET THE TPI TO 0.54 VOLTS ALSO DO YOU HAVE ANY IDEAS

I have a low idle problem on my 1989 corvette

I have had the exact same problem. The fuel pressure regulator is to blame. It acts fine and gives the correct pressures, however when you stop the engine, the pressure within the fuel system pushes past the regulator and leaks into the intake throught the regulator vacuum hose.

I replaced and the difference was so obvious, the car dont run like it is on choke all the time now.

Now the car is fun to drive again.

Get yourself a fuel pressure gauge and check pressure. Sounds like a pressure regulator problem but without testing that's only my best guess. Temperature sensor can also sometimes do that if it keeps sending computer "cold"signal when hot.