Loss of performance or rough idle in 1986-1987 Corvettes is often due to your Corvette Mass Air Flow (MAF) Sensors failure. Replace your failing Mass Air Flow Sensor with a new AC Delco unit. Always replace the Power and Burn-Off Relay with a new sensor.
MAF Sensors measure the air coming into the engine in grams per second. At idle, there should be 8 grams per second.
The mass airflow (MAF) sensor sits between the throttle body and the air cleaner. It measures the incoming air when the engine is running; at idle it measures grams per second. It should be about eight grams per second at idle If you have dirty air cleaner that's not sucking very much air, it's going to change and lean your engine out so you don't flood it. It compensates for everything based on how much air you have coming through there. It has a small burn-off element in it. After you turn the car off it puts 12 V on this small wire for for (5) seconds. It then heats up and burns any impurities off of and it is called a burn-off. As for the cylinder select, that is just in the hardware (the CM) which identifies that you're running a L98 engine and that it's a V8. The firing order is #1, #8, #4, #3, #6, #5, #7, #2.
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