Loss of performance or rough idle in 1986 Corvettes is often due to your Corvette Mass Air Flow (MAF) or more often; the MAF relays.
When replacing your 1986 Corvette Mass Air Flow (MAF) Sensor, replacement of both the Power Relay and Burnoff Relay is highly recommended. Without replacing these relays, you risk possible damage to your new Mass Air Flow Sensor, as well as continued engine trouble codes.
MAF Sensors measure the air coming into the engine in grams per second. At idle, there should be 8 grams per second. The Burnoff Relay has two large orange wires at connecting point. The relay with one wire is the Power Relay