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-   -   PCM and intake (http://www.jeepgarage.org/f108/pcm-and-intake-47614.html)

hollowpoint515 09-18-2012 07:13 AM

PCM and intake
 
My wk2 is completely stock I've had it for about 2 weeks now and I got the jeep fever and i to start making it my own and I've been reading a few different threads and I've heard it from a few people now that the 2011+ PCM automatically "fix" if that makes any sense so if it automatically re-calibrates it self would it even be worth it to put on a new throttle body or intake until a loop hole around this is found? Should i just stick to cosmetic mods until some further development is made like a power programer to get the most out of the intake?

I may not be understand this right either if anyone does know about this some insight would be helpful thanks

FlyinRyan 09-18-2012 05:15 PM

Re: PCM and intake
 
There is some adaptation process, the same kind that exists for changes in temperature, barometric pressure,etc. It doesn't mean the Jeep reverts back to stock power levels or anything like that....Whoever tells you otherwise is full of it. A tune would help

ColdCase 09-18-2012 05:25 PM

Re: PCM and intake
 
The jeep adapts to the stock emissions settings so there is little or no long term power gains. Anyone telling you different is a vendor trying to sell you something. You can get the PCM re calibrated to take advantage of your modifications bat sending it off to one of the tuning outfits, about $600. Forget about the warranty, however.

FlyinRyan 09-18-2012 06:12 PM

Re: PCM and intake
 
Quote:

Originally Posted by ColdCase (Post 685294)
The jeep adapts to the stock emissions settings so there is little or no long term power gains. Anyone telling you different is a vendor trying to sell you something. You can get the PCM re calibrated to take advantage of your modifications bat sending it off to one of the tuning outfits, about $600. Forget about the warranty, however.

It has nothing to do with emissions per se, it's all about fuel trims.

Adding aftermarket parts, whatever they might be, changes the fueling demands of the engine because of the resultant change in volumetric efficiency. So on a fresh PCM reset, the adaptives are not doing anything because there is no prior memory from the O2s providing feedback to the PCM regarding changing what's written in the VE map to reach stoich. Over time, the trims force the actual AFR to be either lean or rich of commanded AFR , be it stoich or otherwise. This is part of the reason why tunes help so much, because the VE map is altered to better suit the needs of the modified setup. Power is still improved without tuning, but diminished some by the large fuel trims swaying the AFR well lean of stoich.

Can't speak for the newer engines as I have not done datalogging on any of them, but the WK1 Hemis from the factory already have trims in the double digits without any modifications. This is likely the factory's way of squeezing mileage out.

Raptor 09-18-2012 09:34 PM

Re: PCM and intake
 
Quote:

Originally Posted by ColdCase (Post 685294)
The jeep adapts to the stock emissions settings so there is little or no long term power gains. Anyone telling you different is a vendor trying to sell you something. You can get the PCM re calibrated to take advantage of your modifications bat sending it off to one of the tuning outfits, about $600. Forget about the warranty, however.


:clap:Werd! Thanks for having the guts to say it!

hollowpoint515 09-19-2012 07:08 AM

Re: PCM and intake
 
thanks for the input im going to have to wait im not spending over 900 to get 10+ hp for an intake that is crazy! ill just wait till a programer comes out then go ahead and get one for now Ill just stick to cosmetic mods

BuckeyeSRT 09-19-2012 08:53 AM

Re: PCM and intake
 
One thing that has not been mentioned that we used to do with the first gen LX's (Magnum, 300, Charger) was pull a fuse (#11 I think) and that would reset the adaptives. We would do this even when we had Super Chips or Diablo tuners. It has not been made clear if we can pull a certain fuse for our WK2's to reset the adaptives but, I would assume that would give you your temporary gains back from an Intake or Exhaust or... I guess you could disconnect the battery but what a PIA that would be.


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