I've had 2 different tunes on 2 different trucks.One was a wait4meperformance tune.The latest was a Nelson.The w4me required a relearn right off the bat.But the Nelson hasn't.Does that determine the aggressiveness of a tune?Whether the engine 'asks' for a relearn or not.Ive been curious.

 

Nobody knows?I was thinking that if a tune is a little more aggressive than stock.Then a crankshaft relearn is not needed.But if the tune is pretty far above stock?Then the engine does need to be relearned to run with the more aggressive parameters.Am I sound in my theory?Or way off.

 

Anytime you change a PCM, crank or cam sensor, camshaft, crankshaft or timing chain you should ALWAYS do a relearn. I've even done relearns on STOCK trucks and noticed smoother idle and better response.

 

Thanks for the reply.I was just going by what I was told when I got my Nelson tune.If no engine light?Then no relearn.I'll get one just to be on the safe side

 

Do the relearn, even with the Nelson PCM.

 

as was mentioned in another post about the same thing....

YES!! you need to get the crank relearn done! especially if it's not the original pcm from your truck originally... do it!

"A CASE relearn is an advanced way for the truck to detect misfires, based on the relationship of the cam position sensor to crankshaft position sensor. Anytime you permanently intend to install a PCM that did not come directly out of your truck, you need a CASE relearn."