Ok I have a 92 Dakota 5.2l 4x4 and I was wondering. I know that the 5.2l performance pcm will work on a stock 5.9l because the advanced timing can suply the 5.9l. With that in mind i'm wondering If that means the two pcm are the same. In other words can I get a 5.9 pcm from a junkyard or something and put it on my 5.2l as a performance pcm? Will it have the same effect as a performance pcm. If so it would save me a lot of money. Any help would be thankful.

 

the software for the 5.9/5.2 is identical. when flashing with dealer software it even uses the same pn

 

So does that mean it will advance my timing like the mopar computer would? will it have the same outcome?

 

5.2 to 5.9 or vice versa wouldn't make a diff in how it runs. the software is the same because the engines are almost identical. they are identical as fas the pcm knows. all the sensors wiring everything is the same. as long as it's mag to mag or la to la your fine.
neither way would be a performance loss or gain unless one has the so called death flash then you'll lose some power. if your current pcm is good though i wouldn't do it.

 

Well actually from personal experience the 5.9 computer is different.
Yes all the basics are the same. The 5.9 needs more fuel/ timing then the 5.2. So if you use a 5.2 on a 5.9 you will not be achieving 100% that the 5.9 computer will give. Yes the 02 and others can compensate for the larger engine needs. But when the engine is not up to running temp it is in Open loop. This blocks all the sensors input and uses a pre determined setup. Also at Wide Open Throttle it does the same. So your not running 5.9's needs, just 5.2 needs.

I have a 5.9Mag that was running on a Mopar Per. 5.2. I finally got a 5.9 Mopar Per. and it did give me a good increase in power. Also with the 5.2MP I was getting lots of pining/predetonation due to not enough advance in the timing. I used 2 step colder plugs and they didn't stop it all. With the 5.9MP it stop them completely.

The stock 5.9 PCM on a 5.2 may help on performance. I say its worth a try if it is cheep. But the Mopar Per. will be best.
A Mopar Per. 5.9 PCM did increase power on a 5.2.

 

Thanks that what i wanted to hear. If i have good results I let everyone know.

 

Kevin, wanting to know if it is good OR bad. Good luck with it.

 

that's interesting crazy. having the same software pn when we flash em i would not have thought that it would make a difference.