LS2 XJ

Cocky bums... Wouldn't ever try that without pulling the front clip, Ive never had good luck with my engine hoist though. Looks amazing...

Well, I would normally pull the grille, but I really didn't feel like cutting off a freshly built cage to pull it off. I have pulled Cherokee engines before without taking it off, so I knew it wouldn't be a big deal.
 
Great swap info Tyler. Thanks for sharing.

When my old 4.0L craps out I may just have to study this option very seriously. Plus I know a guy who can help get it done.
 
B-E-A-utiful!!! I want, I want, I want.
 
so ill need to know the total cost and when i drop my jeep off to get swapped k thankx


sweet build and swap guys should be a beast!!!
 
Nice build so far!!

I can't wait to see it in person.
 
Well, the past few days have been filled with wiring, plumbing, wiring, changing oil pan and bracketry, wiring, trying to figure out an intake system, wiring, cooling system, and oh yeah, did I mention wiring?

Haha, unfortunately she still hasn't fired, but the only thing that I can figure that is causing it is the VATS (Vehicle Anti Theft System). The computer is powering up, kicks on the fuel pump for a few seconds like it should, powers the master engine relay and turns on the injector, coil, TCM, and sensor fuse block, gas pedal works, its throwing codes, etc. Everything seems to be doing what it is supposed to, but the computer is not telling the coils to fire. What bothers me though is that in past experiences with these motors, they will usually fire off and then die half a second later due to VATS, but this one doesn't fire at all. Kinda weird... but like I said, its throwing codes for all kinds of VATS related things (as well as other things such as EVAP and other stuff we no longer have), so I am thinking (well, hoping) that a tune will cure it.

Anyway, I have gotten pretty much everything under the hood all tied together now. I still have to wire up the 2nd electric fan and I need to add a main junction block for power wires, but other than that, shes all done under the hood. I am planning on finishing up the Fan relay tomorrow and then maybe work on his rear axle or the beadlocks, and then HOPEFULLY the tuner can bring his laptop down tomorrow night and remove VATS so I can see if that fixes it. Then, Tuesday it goes to the exhaust shop. Thursday is tying together any engine related loose ends, and then Friday is tuning (if it runs... haha).

Here are some under hood pics:

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From what I learned from my research, the motor will not fire if the VATS has not been disabled.....period.

I have heard it both ways from VATS not being disabled -starts and dies or cranks and won't start at all. Either way it will not run until VATS is disabled. If you have had any programming done the VATS is probably disabled (that is step one in any GM PCM flash for a stand-alone swap). Also, a disconnected ground will cause what you discribe, re-check all of those.
 
Well, I am pretty sure I have all of the grounds hooked up. All of the coils have a ground, as well as the sensors. I hooked up the computer ground too. Everything seems right. We are having the thing Dyno tuned... I always do when I do these swaps. That way we can turn off all of the emissions stuff, and remove VATS. Plus, these engines are pretty "de-tuned" from the factory. On the LQ4 6.0 truck engine I put in we were able to squeeze out an extra 50 HP, just by tuning it.

We expect an easy 450HP out of this one...
 
I don't remember all of them... But a few VATS codes, an EVAP code, had a AIT code b/c the MAF was unhooked, also had a Trans communication code b/c the was a "hole" in the LAN loop (which I fixed), thats pretty much it. Nothing I didn't expect. But with the majority of the codes being VATS related, I am fairly certain that its my problem.
 
Well, today was very successful. I got up bright and early and loaded up the XJ and hauled it about 40 minutes north to a privately owned exhaust shop in Cleveland, Tn. They are awesome at their work if you get the correct guy to do it. One of the guys is an old fart who thinks he knows everything but has proven to everyone he doesn't know crap, nor does he care about doing his work correctly. Anyway, the "good guy" was working today, so we put it up on the lift and I explained what was going on and what needed to happen. They tried to talk me into 2.25" pipe, but considering that the LS2 (heck even the 6.0 truck engines) come from the factory with a dual 2.5" exhaust, I insisted that they do that. After explaining myself and mentioning that this thing makes 400 HP from the factory and will easily be at 450 after the tune, he quickly agreed that 2.5" was a must. Believe it or not, they were able to snake 2 pieces of tubing under the jeep and fit in 2 24" glass packs (this may be temporary, depends on fitment and sound) in the factory location. So, we ended up with a very nice, clean, tight fitting truely dual exhaust that looks like it was meant to be there.

On my way back, I get a call from Novak saying that they had received the gauge cluster and that they would try to get it sent back out next week. Now... I had my own plans for a CEL. I was going to just buy a small LED and put it in the factory jeep hole so that everything would still function as normal. But, there is a problem with that idea. Using an LED wont work b/c the computer doesn't see any resistance from an LED, so it thinks there is no bulb and throws a code for a missing CEL, and therefore turns on the CEL that it thinks is missing... funny, but it does make sense!

So that's where we stand as of now. Tomorrow morning I am going to run down to the local hydraulic shop and have them make up a power steering hose for me so that I can get that all plumbed up before Friday. I also need to run by the electronics supply store and grab a big post style distribution block so that we can hook up some more relays, tie in the alternator, the starter, the factory junction (fuse) block and the winch and then have the 1-0 power cable running to the rear. Right now everything is on the post on the under hood fuse block, and its awfully crowded!

Also, the new Tom Woods rear shaft is supposed to come in tomorrow, so if it does I will probably throw it in tomorrow night after I get back from the Hot Rod Power Tour!

I will see f I can get some pictures of the exhaust tomorrow sometime too. I forgot to do it while it was on the lift.
 
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You should be able to make judicious use of a razor and soldering iron on the gauge cluster PCB and wire the original CEL to whatever you want. Find BL16 on the board once you remove the plastic cover, and while holding the cluster with the connectors at the top, locate the trace on the PCB at about 1 o'clock. Cutting this trace and soldering a wire to the side going to the bulb should allow you to illuminate the CEL by grounding (I think, looks like it's driven by a ground side switched mosfet from my quick scan of the wiring) the wire you just added.

I don't see any way the cluster can tell you did this. There is no monitoring line back from the mosfet (TR15, marked DF RN on top) to the controller IC (IC14, marked TL04231848AA,) so it seems to be "fire and forget" as far as I can tell.

This all assumes it's a full gauge cluster, the numbers are different on a dummy light cluster.
 
Thanks man, it is a full cluster. However, novak will be performing the very same mod you just described while they have it, so I don't need to do anything other than hook up a few wires and go! At least that's what they are telling me...
 
You know... I got to thinking about it, and I used an LED for a check engine light on the 6.0 FJ-40 that I did, and it didn't have any issues with throwing a code for not having a CEL. However, I bet the tuner took care of that for me too. I was just throwing this out there so if anybody else is doing this swap, they know that they can have pretty much anything done with a one off custom tune.
 
You know... I got to thinking about it, and I used an LED for a check engine light on the 6.0 FJ-40 that I did, and it didn't have any issues with throwing a code for not having a CEL. However, I bet the tuner took care of that for me too. I was just throwing this out there so if anybody else is doing this swap, they know that they can have pretty much anything done with a one off custom tune.

I used an LED for my CEL and I didn't do anything except plug it into the PCM output. Works perfectly, will definately throw a code without it.
 
Which ECU/cluster is throwing the code about the CEL light being gone?

Because I traced the wiring on a 97+ cluster (see above posts) and I can't see any possible way the thing can tell you removed the bulb. Maybe I'm missing something but it just doesn't look possible. If it's the LSxECU/cluster on the other hand, I have no experience with that and should probably just shut up :roflmao:
 
Which ECU/cluster is throwing the code about the CEL light being gone?

Because I traced the wiring on a 97+ cluster (see above posts) and I can't see any possible way the thing can tell you removed the bulb. Maybe I'm missing something but it just doesn't look possible. If it's the LSxECU/cluster on the other hand, I have no experience with that and should probably just shut up :roflmao:

LSx, that's the one that will need to be plugged into the cluster.
 
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