this past weekend i installed race longtubes , ory, texas rumbler cat back , ac delco iridium plugs, moroso ultra 40 wires, unscreened the maf , smooth bellows, 160 stat, and a pcm for less tune. Now its throwing this code which is ignition system misfire or problem. To top it off i cant erase the code! Any ideas?????

 

According to the diagnostic list on the GM website:

P1336 = Crankshaft Position System Variation Not Learned.

Sounds sort of "deep"..... "monitor for valid crankshaft error compensation factors"..... "factors are considered not valid if the factor sum is greater than 3.001 or less than 2.9989".

Doesn't appear to be an actual misfire... appears that the system can not reconcile the cranksahft velocity variation pattern its seeing. Way over my head..... may take a GM technician to sort this one out.