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Wolfknight87
July 23rd, 2008, 12:43 AM
I am trying to swap out my stock 3.1L for a 3.9L from a g6. My two options are to use the stock OBD1 system or to use the wiring and ecm that came with the new engine and then retain the vvt functionality. If I use the newer ecm what would I need to make it work? Can I disable bcm functions and just use a g6 gauge cluster and wiring? Any insite would be greatly appreciated!
GMPX
July 23rd, 2008, 11:04 AM
What year to what year?
If you are putting say a 2007 3.9L in a 2002 car then it's really all too hard.

Cheers,
Ross
Wolfknight87
July 24th, 2008, 12:17 AM
I am swapping the motor into an 90 beretta which has the obd1 computer, but I am pretty much gutting the car anyway. I am using the g6 6spd and 3.9L engine combo. My biggest concern is the drive by wire system. I have an adapter to go to a cable driven throttle body, but would it be possible to delete the drive by wire function out of the computer and wire in a tps sensor instead or am I stuck with drive by wire if using the 3.9L factory ecm?
GMPX
July 24th, 2008, 12:33 PM
If it is the E38 or E67 ECM (you never said which year the 3.9L came from) then you are stuck with Electronic Throttle only.

Cheers,
Ross
Wolfknight87
July 25th, 2008, 10:23 AM
I believe its an e67, but I can't confirm it. I've looked at part numbers but can't find a match for 12602257. Either way what all would I need to get this working with the g6 computer setup? Obviously the ecm, engine wiring harness, and now an electronic gas pedal. Two main reasons I would like to go through all the trouble are to retain the vvt functionality and also so I have a good base tune to start with where as if I go obd1 I will be starting in the dark more a less.
ScarabEpic22
July 26th, 2008, 06:32 AM
From what Ive read, you are going to need to keep the ECM, TCM (they are seperate on the G6s) and the gas pedal so you can drive your ride.

Also, its a 3.9L? Pretty sure they only offer a 3.5L and 3.6L in the G6???
Wolfknight87
July 26th, 2008, 08:56 AM
They stopped putting the 3.9L after 2006, and went to the 3.6L dohc. Kinda wish I would've held out for that to swap in, but it seems like more of a nightmare. Also I forgot to mention I am using the 6spd manual gearbox and not the auto.
ScarabEpic22
July 26th, 2008, 06:59 PM
Ah, either way you are gonna need a TCM or a PCM that controls the trans. Good info though, didnt know GM put a 3.9L V6 in the G6 a while ago.