my iroc sits quite a bit in the garage , used as a sunday cruiser , i have found that under hard xlr8 the engine light comes on , the engine pings , and smoke( gray i think ) is exhausted , not sure when timing has been touced last . could this be running to advanced ? starts up fine , also has had mass air flow sensor codes come up but always resets . any ideas or adjustments i could make

 

Check your timing first. You could have too much total timing. As long as the engine isn't modded heavily, disconnect the MAF and give it a shot (after you check timing), be gentle, detonation isn't fun.

 

What octane gas are you running?