Hey everyone!!!! It's me again...still getting info. on the 5.9 mag. swap...is the 5.2 ecm the same part number as the 5.9 magnum??? Also, if i get a ecm for the 5.9 mag. will i have to get the ecm from that engine or can i get any 5.9 ecm??? Does the used ecm need to be flashed or reset or reprogrammed??? Don't know too much about the ecm set-up on the autos...???

 

The part numbers are different between the two. You can use any 1997 or similar pcm for a 5.9, just make sure it is for an automatic (IIRC, yours is an auto, right?).

I don't know if an OBDII computer will complain or not... I haven't had much experience with them. I would think if the pinouts are the same, it should work fine.

Honestly though, the 5.2 computer will run the 5.9. It won't give you full power from the 5.9, but it will run it... so if you can't find a computer, don't let that stop you from the swap. Swap the engines and run it off the 5.2 computer until you can find the computer you are looking for.

I'm running a 1995 Dodge Ram 5.9L mopar performance computer on my 1995 Dodge dakota 5.2L and I haven't had a single problem with it. In fact, the fuel curve and more specifically the WOT fuel curve gives my slightly modified 5.2L a little bit extra over the 5.2 MP computer.

 

I swapped a 97 Ram from a 5.2L to a 5.9L. Ran better with the 5.9L PCM because it got the proper fuel curve for the added cubic inches.