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Green Bay XVL
02-18-2011, 11:05 PM
In order to put my tuned pcm into the car, i need to replace the other one. (Obvious)
But what i need to know, how the hell do you get the old pcm out of the bracket? I can unclip the 2 wire harnesses but i cant get the connectors that are sealed unplugged.

Help Would be very welcomed!

AaronGTR
02-19-2011, 08:31 AM
Not sure what you are unclipping... there is nothing to unclip on the wire harness. The covers stay on the plugs. There are two main connectors on the the bottom of the pcm and each has a bolt in the middle (7 or 8mm I think). You loosen those up and the connectors pull straight out. Pull back the plastic clip that holds the pcm in and it drops right out.

johnnygt02
03-05-2011, 08:22 AM
what all does a pcm do to the car? does it change how u have to drive? or just makes everything better?

AaronGTR
03-05-2011, 02:47 PM
what all does a pcm do to the car? does it change how u have to drive? or just makes everything better?


The PCM controls everything that the engine and transmission does. A tuned PCM usually will have a sportier more aggressive shift program, and a slight increase in engine power and response. Just how much power depends on the options you pick and what fuel grade you want to run, as too how much ignition timing they can add. There are also other functionality options such as turning off rear O2 sensor codes and such if you have installed a high flow cat in the exhaust, so that you won't get any check engine light from that. That's just one example.

johnnygt02
03-05-2011, 05:00 PM
so if i bought a pcm i couldnt just put it in and bam it works? u have to program it or some1 else does?

WidbyJ
03-05-2011, 06:09 PM
You got it. All OEM PCMs work about the same. To actually change anything you need to have it tuned by someone who has the proper equipment AND knowledge -OR- buy an HPTuner setup and learn how to use it properly. It could be pssible for someone with another identical car to tune the PCM for your use and then send it to you ready to run, I believe MPRacing does this.

Older cars could have the 'chip' swapped for better performance, these cars do not work that way.

AaronGTR
03-05-2011, 08:23 PM
so if i bought a pcm i couldnt just put it in and bam it works? u have to program it or some1 else does?


If you buy a PCM that is pre-programmed for your car by a tuner such as MP racing or Milzy Motorsports, then yes you can put it in right away and it will work. If you just buy any old stock PCM, it must have the correct program for your car in order to run, and well... it will run like stock.

One thing to note though. Even if it is programmed for your car, there are still a couple things you must do after installing. There is a security feature built in that matches a randomly rotating code with a code in the BCM, that sends power to the fuel pump and allows the car to run. If those codes don't match up you must do a security re-learn procedure (which basically lets you start the car once) then take it somewhere to get the security fault code erased from the PCM. Otherwise the security light will stay on and it won't let you start the car every time without doing the security relearn procedure every time (which takes about 10min). Also you must get a CASE learn done. This lets the PCM record information on the crank shaft position sensor so that it knows what position the crank is in, in order to control ignition timing.

johnnygt02
03-06-2011, 04:31 PM
wow sounds like too much maybe ill pass

ikilledyooouuu
03-07-2011, 07:18 PM
wow sounds like too much maybe ill pass

Not really...

johnnygt02
03-09-2011, 04:22 PM
whats the easy way to do it because your talking to a noob