Will a wiring harness from a 5.9 Dodge work in my TJ?

lostintime

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So one the jeep I just bought I found out that the engine is out of a 98 Jeep Grand Cherokee 5.9L. My question is will a 98 dodge 5.9 harness connect to all the connections I need eg trans plug, ect, dist. and all others?Or do I need to find a harness from a 98 jeep again?
 
My guess would be there are different connections / connectors. It's only a guess, but I'm fairly certain this is going to be a tough one for most to answer.

Maybe @RangerRick will know.
 
So one the jeep I just bought I found out that the engine is out of a 98 Jeep Grand Cherokee 5.9L. My question is will a 98 dodge 5.9 harness connect to all the connections I need eg trans plug, ect, dist. and all others?Or do I need to find a harness from a 98 jeep again?

To the best of my knowledge yes you can use a wiring harness from a 98 Dodge pu. The one issue will be that the starter on the GC engine is on the passenger side and on the Dodge truck it is on the drivers side. Most people use their TJ harness and blend the needed wires from the donor engine into the TJ harness. A lot easier than trying to strip out all the unneeded wires from the truck harness.

This is a VERY imformative thread on doing the Magnum swap into a TJ and the folks in this thread are very helpful.

https://www.jeepforum.com/forum/f9/wrangler-magnum-v8-discussion-1365878/
 
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Ok I did the wiring harness as I bought a 98 dodge harness married to a 98 grand cherokee 5.9 and a cherokee ecm. Now it starts and stalls constantly. What am I missing?
 
Well because the Cherokee ECM is for a 6 cyl engine and you have a V-8 for one. And if I remember right the Grand Cherokee has the SKIM feature.
 
Okay when you say Cherokee I am thinking XJ type Cherokee not ZJ Grand Cherokee. And yes if it starts and almost immediately dies it is either your SKIM or ASD relay. For the SKIM you either need a different ECM or get your current one reprogrammed.

You can get a ECM from a Dodge or Dakota pu but check that it doesn't have SKIM. If you get a ECM from a 5.2 you can get a flash from Flyin Ryan or HemiFever to adjust it for a 5.9. This is what I am going to do with my current ECM. I will just get a new flash for it when I get my 5.9 built. I currently have a 5.2 in my TJ. The 5.9 will run on the 5.2 tune but it will run lean.
 
I think yes there is but I am not 100% sure. Contact Flyin Ryan or Hemifever as they are the two people I know who can tune the ECM on our Jeeps. Depending on what you have done to your 5.9 you are going to want a tune for it anyhow. Even people without any engine mods have gained HP from adding one of their tunes.

And just a little plug, I've got some performance parts I have taken off my V-8 if you are interested.

https://www.hemifevertuning.com/Default.asp
https://www.hemifevertuning.com/category-s/91.htm
https://www.frptuning.com/
http://www.frptuning.com/product-p/sct9603.htm
If they can't do it then the other place is B&G but you have to send them your ECM.

http://www.bgperformance.com/
http://www.bgperformance.com/jeep-tuning/
I would contact each of them and make sure which one can handle what you need. I have a ECM tuned by B&G but also have a SCT handheld that Flyin Ryan is going to do the tuning on my 5.9 when I am done with it. I'm building a stroked 5.9 which makes it a 6.7.
 
One thing to know is that you will need to is a wide band O2 sensor. You will have to collect the data from it to send any of these companies so they can see what your engine is doing. But many of the people I have talked with on Dodge forums have reported great results from their tunes. Also from talking with guys who have done the V-8 swaps on their TJ.
 
SKIM system didn't come out till 2001 in the Dodge Dakota so since it is older than that it should work.
 
My understanding is the it shouldn't have a chipped key. SKIM is the security part that the chipped key talks to.
 
Okay I don't know for sure why the Dakota PCM won't let it start now. Have you checked all your voltages at the power distribution block? Is your ASD relay getting power? I have a known good PCM I could send you to test out but I would need it back. The first two PCM's I got were bad and I ended up buying one off Ebay. I actually bought a spare but have never tested it to make sure it is any good.
 
Okay I don't know for sure why the Dakota PCM won't let it start now. Have you checked all your voltages at the power distribution block? Is your ASD relay getting power? I have a known good PCM I could send you to test out but I would need it back. The first two PCM's I got were bad and I ended up buying one off Ebay. I actually bought a spare but have never tested it to make sure it is any good.
I will have to go over everything again tomorrow