CASE relearn

[5xBuckman]

So I have successfully swapped the 4.2L in my 05 TB....thanks in large part of the information on this site!

My question now is about the CASE relearn that all sources say need to be done on an engine swap or if you move the crank position sensor.

It did note that there are people that claim the '02-'05 engines aren't as fussy '07 and up. And that you might not generate a MIL.

But, should I get the CASE relearn done even though there is no trouble code? A local shop will do it for $50.

Thanks...Dan

 

[littleblazer]

I'd say you should have it done. It makes it easier in the event of a misfire but if there is no light it may be okay. If you used the donor pcm it shouldn't need it.

 

[HARDTRAILZ]

I swapped PCM and did not do one for a few months with no light, but did do one eventually just to be certain there were no issues

 

[Mooseman]

The other name for this is "Crankshaft Variation Relearn". Yours might be within the same variation of your previous engine or you used the PCM from the replacement engine?

No CEL or code, I'd leave it. If you ever run into a friend with a Tech 2 or high end scanner that can do it, then do it. IIRC, the PCM uses the camshaft sensor to compare against and if it's off, then the code sets.

 

[limequat]

For $50 bucks I'd jump on it. MY2005s rarely set the code, but your timing could be off. This could manifest itself as the evil P0300, reduced power, or reduced fuel economy.