pcm help

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hilljob26

9/7/2007 3:45:44 AM

ok,we are wanting to get our pcm retuned,for all of those who did it,what exactly had to happen,i know i have to send it in,but my question is,when i get it back,can i do everything right there at home,or do i need to take it to a dealer,there isnt a hummer dealer around here except for kansas city,and that is 3-4 hrs away.this is something that is a must as i am wanting to add bigger tires,and that poor little 3.5 really could use a little bit more,all help would be great

Doc Olds

9/7/2007 5:38:48 AM

Well it depends on which option you use. If you go with a loaner, it is one of the easiest modifications you could ever make to any vehicle, right in your own driveway. If you would search "PCM" or PCMforless, you will have volumes of reading to answer your question. http://www.hummerforums.com/m_18248/tm.htm from HummerGuy, and better yet, http://www.hummerforums.com/m_21150/tm.htm from kelly@pcmforless. PM Kelly if you have further questions.

alrock

9/7/2007 9:16:00 AM

Hilljob, I just did it a few weeks ago. 1) Order the loaner option. 2) Remove original PCM, install loaner, do security relearn. 3) Ship off original, get it back within a week. 4) Put original back in, return loaner. 5) Smile with the improvements and performance gains! And read the other threads about the details that I'm glossing over. Once you figure out how the PCM is latched in, it's just a few minutes of work at each change. No dealer involved, no downtime.

Doc Olds

9/8/2007 6:16:33 AM

If you do the loaner program there is no CASE (Crankshaft Angle Sensor Error) relearn! The only time that is necessary is if you do the Core Exchange. If you get that error you have the dealer do a rescan, actual scan time is very short, but depends on how busy and cooperative your dealer is.

The loaner program is very easy. See alrock's quikee over view above. Piece of cake.

Doc Olds

9/28/2007 9:30:14 AM

The consensus seems to be 0 improvement for a very few (enjoying a boost in power

and heavy with the foot) up to some reporting 3mpg improvement?? Still, if you increase the drivability of the 3, and can improve mileage by 1-2mpg. No brainer. Everyone agrees that it takes a couple of tanks of gas to see all the improvement because of two things: 1) getting your foot out of it like you astutely observed; 2) PCM learning after the tune, takes at least 500 miles or so.