86 corvette
2 Answers
Possible low fuel pressure, just change out the fuel filter and check fuel pressure, possible Ignition Control Module, once the engine heats up, when the ICM starts to break down the engine heat can affect it. This can be tested at Auto Zone if you take it out. Also check for vacuum leaks, throttle body base gaskets, intake gaskets, spray carburetor cleaner along the gaskets, if there bad the RPMs will pick up.