1988 Chevy Corvette Running Rich

Most common problem with this engine is faulty mass air flow sensor and also the 2 relays, power and burn off. The bad mass air flow gives the computer a false air intake reading causing rich condition. Also double check ignition timing. If its off and it has not been adjusted recently then suspect a bad shaft inside the distributor causing timing to change. There are so many possible causes for this problem. Using a scan tool I would monitor coolant temp sensor to make its accurate because this also effects fuel air ratio. O2 sensor is very importatnt on this engine and double check the grounds at the thermostat housing, this is the computer ground.