Newly Cammed LT1 Runs Poorly In Closed Loop
Recently I installed my CC503 cam with all the supporting mods, (Ultra Pro Mag rockers, hardend pushrods, Comp 918 springs, etc). For now I have a tune from MadZ28. Initially the car started right up and idled perfectly. However on my first drive I noticed that it suddenly took a turn for the worse and started backfiring, and popping and would barely want to move. I brought it back and scanned it while running and noticed an insane amount of knock, which I presumed was being detected from the new rockers and valvetrain noise, which in turn was retarding the timing. So I ordered a LT4 knock module and adjusted the valves correctly.
I put the module in and it started right up again and seemded to run better. I went to go around the block after it warmed up and it started popping and backfiring once again, exactly like it had. I scanned it again and noticed there is a constant 4 degrees of retard at idle and slightly less but still alarminly high knock count (7k now 22k before).
The Opti in the car has maybe 5k miles on it and it 2 years old. The ICM, anc coil are both relatively new as well (last 2 years). It is a night and day difference between open and closed loop tough so I am figuring it has to be some type of sensor that doesnt activate until its in closed loop. I am not sure where to go from here so any help would be appreciated. Thanks guys.
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1994 Z28 A4, Magnaflow, TTII'S, CC503, 1.6' RR, MadZ Tune, Pacesetter Lt's, 3'' ORY, K&N CAI, Free Mods, Nitto Dr's.
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