96 to 99

[beraad44]

im wanting to swap in a 99 4.0 into my 96 4.0. what all would be involved to do so. i believe there is a problem with the distributor maybe? Any info will be appreciated.

 

[cdnabn49]

I was looking at a 99 swap too... here is some information from fargoXJ from Edmonton Jeep Club...
hope this helps.

I found this posted about using the 99+ intake on an earlier motor. The section for you would be the injector harness modification to fit the newer injectors.

http://www.go.jeep-xj.info/HowtoIntakeManifold2.htm

http://bb.bc4x4.com/showthread.php?p=863296

 

[beraad44]

This is Beraad44's father. I just got back from looking at this engine. It does not have a distributor but has in its place what I assume is a ign trigger that goes in just like the distributor and has wires attached. Will the dist go in in its place?

The intake and exhaust is different. Is it safe to assume that the 96 parts will bolt up?

Thanks for the links. I'll check them out when I get time to sit in front of a pc.
Thanks.

 

[winterbeater]

I believe it will all swap out. You might want to check the head. Casting # is on the top near the middle on the manifold side. If it says 0331, you might want to search out 0331 casting cracking info. Very common issue.

 

[badron]

I would do a little more searching. But this may help some, You will need the 99 flywheel/flexplate. Your 99 uses a sensor mounted in the bellhousing to tell the computer when to fire the plugs. That thing in the 99 in place of the dis tell the computer when to fire the fuel injectors. and needs to be installed in the 96 motor. I DO NOT KNOW IF IT IS A DROP IN. More info is needed in that mater. You may also run into other sensor incomparability. I often just switch all sensor just to keep it simple Bring the intake over. The 99 intake rules. This will also insure the right Injectors, TPS etc. You should only need one coolant temp sensor the one mounted in the t-stat housing taken from the 99.
If your 99 has the 3 cat system then you may have some real work. A SH## load of O2s must be retained in order to stay complaint in all 50 state and the district of Columbia. From what I have read the differences in EX ports make just bolting up the 3 cat system to the 96 head impossible. Some one else is going to have to help there. LUCK

 

[winterbeater]

The 96 exhaust ports are bigger than the 99. Seems like it wouldn't hurt to put the bigger header on the smaller head (but not the other way around). The 96 also has the Crank Position Sensor already. I agree with changing out the sensors to maintain compatability with the PCM/ECM.

 

[beraad44]

If your 99 has the 3 cat system then you may have some real work. A SH## load of O2s must be retained in order to stay complaint in all 50 state and the district of Columbia. From what I have read the differences in EX ports make just bolting up the 3 cat system to the 96 head impossible. Some one else is going to have to help there. LUCK

Does this mean that I cannot put the 96 exhaust and intake on the 99 engine because it will not fit the head? And if it would work with the engine would the exhaust sensors still be a problem? If I use the 96 intake and exhaust the cpu will match and I would think the two exhaust sensors would be fine.

I'm trying to use as many 96 parts as I can so I'm thinking if I do that everything will match up and will be compatible with the cpu in the 96 cherokee. Of course I still need to find out about the distributor. If I cannot use a distributor I can't use the engine at all.

 

[winterbeater]

I haven't done it myself, but from what I understand the exhaust manifold and distributor will fit the newer block. Hopefully someone who has actually done it will verify.

 

[badron]

Sorry I had thing a but mix up before. It's a 99 engine going into a 96 Jeep. Don't get old the mind is the first thing to go. Sorry again. Keep the 99 intake on the 99 engine. The 96 and TPS MAY need to come over. The injectors are not the same but may work anyway. The 99 motor has one coolant temp sensor. I THINK you 96 has two. No hole in rear of head for one. Sorry I don't know of an easy work around other then drilling and tapimg the hole. The flat spot fore the hole is there on my head. Or switching heads. Switching head would also fix any ex problems ( if any) as well as getting you a bigger poop port. The 99 intake will bolt up to the 96 head with the 96 gasket. The voltage regulator is internal to the computer for the alt on the 99 motor but not on the 96. Switch alt would be easy/safest fix. Your dis will need to come over but I still don't know if it's a drop in. Sorry for any trouble with my first post.