does anyone know how, because i have access to a tech 2

 

Jesse posted on fullsizechevy forums on how to do it. Its in the 100$ tune thread. I would link it for you but that thread is probably very long now and I can't search. I wanna say it was around page 10 but don't quote me.

 

My service manual says to enable the Crankshaft Position System Variation Learn Procedure with the engine in operating temperature, the truck in park or neutral, and the scan tool connected...I'm assuming there's a prompt for it on the screen. Slowly raise the engine speed to 4000 RPM and immediately release the throttle when engine speed decreases. Turn off the ignition for 15 seconds after the learn procedure is completed successfully. (basically bounce it off the rev limiter)

**EDIT** You must first clear the code before performing the procedure...

 

I can scan and email the page in the service manual if you'd like...

 

The process that I have used is

Try to crank the truck... It will not fire leave the key in the off position for 11mins (no less, but more is ok)

Then turn the car off for 30 seconds (more is ok, but no less)

Repeat that 3 times... It will fire on the fourth...

 

that's the security relearn procedure...

 

i got a crank code in mine (P1136) and i have like no power above 4,000rpm, is this normal, or do i have another problem on my hands ?

 

Yea, the crank variation can definitely cause that...the first time I had that issue my truck wouldn't even idle, I guess it just matters how far off it is. (I had the same code on 2 different PCM's, the second time around it ran fine but just threw the code, the first time the truck felt like it was running on 6 cylinders)

 

Oh I thought it was all the same thing!!!!!

I was wrong!?!?!? sorry

 

yeah, mine seemed to shift really funny too, and it gave me some missfire codes high in the rpm range, do you think that will go away with the relearn? thanks for all your help