2002 rcsb 4.3 to 4.8 swap issues.

[Frenchy]

Still sounds like VATS. Know anyone with HPTuners or EFI Live?

[farmtruc]

like he said above, it's definitely vats. there is also security in the ignition switch.

you can try this
http://www.nelsonperformance.com/passkey.htm

and if that don't work, you need to get the pcm to someone who can disable vats.
Even in the future, I bet he will always have an issue with vats, it's a very picky system, so just get vats disabled in the pcm.

send me the pcm, i'll do it for $25.


later,
allen

[chevyracer8262]

Thanks's alot everybody after he finally showed me the reciepts for everything that he bought I realized that everyone was correct about the VATS system it is the issue. Turns out that all the parts he bought, engine, transmission, wiring harness, Pcm, steering column, instrument cluster all came from different vehicles cause the reciepts had the vin no's for all the trucks they came from. So the ignition switch is the wrong switch for the vats system. So Mr farmtruc that pcm will be on it's way to you Monday with a note and mine and the truck owners contact information.

Thank's again everyone.

[decibles]

Ok just to add my two cents also. The vats system is fairly simple to relearn no matter what module you replace and equally as easy if you replace every module. I find it difficult to believe that dealership would not do a complete relearn on the security using the techII. If in fact you were in a security fault situation the security light in the ipc will be flashing, and yes you will have a PCM DTC which is described as VTD fuel disable. Granted Snap-On may not have the ability to see all of the factory DTC's, I really can't say I have zero experience with there scan tools. I also want to remind everyone that there isn't actually a chip in the key on these systems, as stated above the ignition switch is the component for providing the IPC with the security signal although this is not application specific it is a generated signal based on time of pulse as the ignition is cycled from off to on. If you were to perform the security relearn properly the signal sent will be the only signal recognised from then on. I hope this may clear up some confusion on the VATS which is Vehicle Anti-theft System and has seen many different methods of providing vehicle theft protection including keys with chips which were very problematic and not very secure.

Shane

[chevyracer8262]

Well we got the pcm back from Nelson perf after getting the vats system disabled and we finally got it to run, but it won't idle. What could be some common causes for this engine not to start when the throttle blades closed? It'll start with the throttle partly open but if you let off for it to idle it dies.

[pl4yboy]

Well we got the pcm back from Nelson perf after getting the vats system disabled and we finally got it to run, but it won't idle. What could be some common causes for this engine not to start when the throttle blades closed? It'll start with the throttle partly open but if you let off for it to idle it dies.

Relearn TPS?

[chevyracer8262]

yes it turned out to be a relearn situation, he's started it several times since we got it running and now it's idles fine, just had to relearn the sensors. thanks again, now i can move on to my 94 s10 383 project finally