[2002HeavyChevy]

So I decided I might try going back to the stock pcm to try and see if my gas mileage increases a little on the highway and possibly send out my "tuned" one to be try another tuner. I replaced the wait4me with the stick unit and now the truck wont run. Turns over and i get it to try but it immediately dies. Any thoughts?

P.S. I've heard a little here and there, and I always do a search but have others had nominal results, almost like the tune was great in the beginning and slowly just fell on its face. Truck does get up and go better than stock but no where near as good as when i first put the tune in....any thoughs here?

 

[lowgreen01]

Your tune "going away" doesn't make sense. A tune is a cut and dry program and is set to react to certain conditions(weather,Throttle position, fuel, air, etc).

If your truck is pulling timing because you're getting knock then that may be why you're seeing decreased performance. If you never did a crank relearn then that's another reason why it might fall on its face.

 

[Denaliano]

Security Relearn?

 

[Denaliano]

The typical 1998+ Car and Truck Passkey/Antitheft relearn procedure is this:

1. Disable your headlamps. Attempt to start the vehicle. Vehicle may or may not 'fire' and quit. Some vehicles will not engage the starter. This is normal. DO NOT TURN OFF KEY YET !!

2. Leave the key in the "on" position, until the 'security' light goes out or quits alternately flashing between "Security" and "Battery". This relearn period always takes 10 minutes. How long does this take ? 10 minutes. How long do I have to wait ? 10 minutes.

3. After security light is no longer displayed, shut the key off ! Wait 5-10 seconds and repeat the above procedure (steps 1 through 3) another two completed times for a total of 3 start-relearn-attempts, remembering to shut the key off between each 10 minute relearn procedure. This will take 30 minutes--no less. If the 4th start attempt fails to start the vehicle you did one relearn step (or all of them incorrectly). If you left your headlamps on until the battery went dead and voltage dropped below 10.5 volts, no amount of relearn attempts will be learned !!

Don't read too much into this. Most people cannot seem to grasp the simplicity of this relearn procedure.

 

[2002HeavyChevy]

This i shall try. I'll keep you posted how it goes...

 

[justinp95]

Mine started and died the first time i tried, but then i just tried again it started fine. Should I still do the relearn?

 

[xlcooplx]

look for something that robbie797 (i think) posted. he had the security problem:imo