OP
Im still gonna be working on more pictures and details soon. Between Christmas and other projects I have not had the chance to work more on this writeup.
How To LS Swap Your TJ
- Thread starter XCRN
- Start date
I also would like to hear about this one.
And @XCRN , great write up!
I was thinking Magnum V8 but this has me looking more closely at the LS.
I won't spoil the story since I don't know all of it...
He's done a great job and from the pictures it's a clean install. As others have said I like his solution for the air cleaner box too.
For a pre 2003 TJ I'd still look at the Magnum V-8 due to it being less complexity. You only have to run one PCM and it's a 14-20 wire blending & the two harnesses blended & the Dodge PCM talks to your TJ dash. But I can also see the reasons for doing an LS swap.
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I like this post. Too bad you can’t help me figure out how to get mine working correctly. Paid a shop to do it and they had it for 15 months and still can’t get it working correctly! Can’t pass emissions mpg is worse than the 2.5L which I find strange. They added gauges because they couldn’t get the stock ones working correctly. Have lots of electrical gremlins now because all the sudden the gauges will work and then go off again. They also unhooked all my LED lights on the front and my winch… I wish I had the time I think I could have done it all myself. Oh and they used Novak parts, wiring and programming and still couldn’t get it working right even with the step by step information they supplied.
OP
PM me and I can see if I can try and help with what I can. Sounds like it could be a tuning issue. My first version of this build I used a Terminator X for engine control and the base tune it gave you ran horribly rich and got like 7mpg. After having a professional tuner mess with it and give me a better tune to start with it jumped closer to 15mpg. Don't think I would be able to help emissions as much since I did not need to worry about that. Is the motor built at all?
You'll have to PM him since he's a new member & isn't a supporting member.
@5632 can you maybe help him out with the shop near you that did your LS swap? Looks like he is in need of some good help.
I would pm you but as Wildman said I am new here and not a supporting member.
Thanks for the quick reply and yes, I am sure the programming has some or maybe even a lot to do with the problems. I am not going to divulge the name of the crappie shop who said they could do it and do it in a month and it took a year the first time I got it back.
Got 2 miles away check engine lights and it kept stalling. 3 weeks later got all the way to my neighborhood and a repeat of the first time. another 3 weeks and they brought it to me, and it started acting up as the got into my neighborhood as well. So I told them they should have just turned around and what was the point of stopping at my house.? The last time I had it two days and finally had a chance to do emissions and the damn light came on while in the testing bay. I know this much I can fill my tank and ill average roughly 7-8 mpg and I am currently only driving it to and from work. I expected 15-20 mpg with a bigger motor.
I have put an OBD2 reader into it that reads through Wi-Fi to my phone, and I screen shot the problems and spoke to a few other mechanic's and have done a couple of things they suggest. Every time I reset it after I do something I literally get it to the point it is technically ready for emissions and the lights come on. We have decided not to take it back to the shop because one of the things wrong with it consistently. They love to do is blame Novak who hasn't worked on the vehicle physically only verbally or through email with the shop I used. They have never taken any responsibility for anything that's gone wrong or delayed completion.
We are currently speaking to a lawyer about legal action due to them messing up a vehicle that worked a 100% not one thing wasn't working when I dropped it off. It was a 1 owner and had 69K miles with a 2.5L v4 with the ax5 5speed. The heat and AC worked but with the bigger tires I put on it during the summer it would cause it to overheat on long runs. I wanted to originally put a 4bt or TDI in it but the shop that said they could do that stopped responding to my emails and phone calls. So, when I came across another shop who quoted me the same or relatively the same price to do an LS3 5.3 V8 I said hell ya.
Now we have lights that don't work and gauges that don't work. Plus 3 new gauges they charged me to add so I would have voltage, oil pressure and temp....all because they couldn't get the dash gauges to work. I put a short throw shifter with an offset to clear the center console and dash because the almost busting my knuckles to shift every time really sucked. I honestly have been considering just pulling both computers and wiring harness out and buying the Holley EFI Terminator X Max gen 3 for gm trucks and installing that to make it all work. Probably not because that's really expensive and I'll have to register it out of town (no emissions that way). The lights and winch I can reconnect myself when I get around to it.
I work a lot (Truck driver) that's why I hired someone to do this job. I have considered having another shop maybe an electrical pro to see if he/she can master the repair, but I have so much money already invested into this jeep I'll never be able to sell it without losing my ass. Plus, I am not sure I want to invest as much as it might cost to pay someone with the expertise to fix it.
Thanks for any advice.
Thanks for the quick reply and yes, I am sure the programming has some or maybe even a lot to do with the problems. I am not going to divulge the name of the crappie shop who said they could do it and do it in a month and it took a year the first time I got it back.
Got 2 miles away check engine lights and it kept stalling. 3 weeks later got all the way to my neighborhood and a repeat of the first time. another 3 weeks and they brought it to me, and it started acting up as the got into my neighborhood as well. So I told them they should have just turned around and what was the point of stopping at my house.? The last time I had it two days and finally had a chance to do emissions and the damn light came on while in the testing bay. I know this much I can fill my tank and ill average roughly 7-8 mpg and I am currently only driving it to and from work. I expected 15-20 mpg with a bigger motor.
I have put an OBD2 reader into it that reads through Wi-Fi to my phone, and I screen shot the problems and spoke to a few other mechanic's and have done a couple of things they suggest. Every time I reset it after I do something I literally get it to the point it is technically ready for emissions and the lights come on. We have decided not to take it back to the shop because one of the things wrong with it consistently. They love to do is blame Novak who hasn't worked on the vehicle physically only verbally or through email with the shop I used. They have never taken any responsibility for anything that's gone wrong or delayed completion.
We are currently speaking to a lawyer about legal action due to them messing up a vehicle that worked a 100% not one thing wasn't working when I dropped it off. It was a 1 owner and had 69K miles with a 2.5L v4 with the ax5 5speed. The heat and AC worked but with the bigger tires I put on it during the summer it would cause it to overheat on long runs. I wanted to originally put a 4bt or TDI in it but the shop that said they could do that stopped responding to my emails and phone calls. So, when I came across another shop who quoted me the same or relatively the same price to do an LS3 5.3 V8 I said hell ya.
Now we have lights that don't work and gauges that don't work. Plus 3 new gauges they charged me to add so I would have voltage, oil pressure and temp....all because they couldn't get the dash gauges to work. I put a short throw shifter with an offset to clear the center console and dash because the almost busting my knuckles to shift every time really sucked. I honestly have been considering just pulling both computers and wiring harness out and buying the Holley EFI Terminator X Max gen 3 for gm trucks and installing that to make it all work. Probably not because that's really expensive and I'll have to register it out of town (no emissions that way). The lights and winch I can reconnect myself when I get around to it.
I work a lot (Truck driver) that's why I hired someone to do this job. I have considered having another shop maybe an electrical pro to see if he/she can master the repair, but I have so much money already invested into this jeep I'll never be able to sell it without losing my ass. Plus, I am not sure I want to invest as much as it might cost to pay someone with the expertise to fix it.
Thanks for any advice.
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Sorry to hear about all the issues that you're having with the swap. I can sort of relate since the shop that did my Magnum V-8 swap didn't get mine right either. And they were over 10 hours away from me so I wasn't taking it back to them.
I was able to get mine fixed mostly but always had drive ability issues. It ran rich to the point of clogging the cat at one point.
I hope you can get things figured out on it. You might try contacting Novak yourself to see if they can talk you through some diagnostic procedures?
I was a OTR driver for a few years myself so I know home time is limited and working on your rig isn't always #1 priority.
I was able to get mine fixed mostly but always had drive ability issues. It ran rich to the point of clogging the cat at one point.
I hope you can get things figured out on it. You might try contacting Novak yourself to see if they can talk you through some diagnostic procedures?
I was a OTR driver for a few years myself so I know home time is limited and working on your rig isn't always #1 priority.
What year is your Jeep?
One big indicator that the original shop had no experience in this swap is that they must have originally thought the stock gauges would work with the LS. I’m not and LS expert, but I don’t believe they will (someone correct me if I am wrong), and would require new gauges. The only way to get the stock gauges to work is to throw in a Hemi - or perhaps a Magnum (Wildman will know this), and even then only certain years of the ECU can be made to work.
Good luck getting it sorted - lot’s of experience here to help.
I'm going to guess 2002 or older since he states it had a 2.5 4 popper in it. Which would have made it a perfect candidate for a Magnum swap.
From what I know of the LS swap into a TJ you can keep the stock gauges but have to run both PCM's to do so. You need a oil pressure sensor and water temperature sensor for the Jeep PCM and the LS PCM so you have to figure out how to mount both.
Then you also need a emulator for the tach to function properly.
This is why I'm not a huge fan of the LS swap unless you're going to run full aftermarket gauges which adds $$$$ to your swap. I might be mistaken about this but it's what I've read which is limited.
Supposedly you can just run the appropriate senders to the stock pcm. I had heard of a magic box that can convert gm signals to something the stock dash can use but i don't remember where i heard that.
The draw for me of an ls swap besides price would be going with a cj style flat dash and scrapping all the wiring and plastic. Then just run a hotrod hvac.
Basically treat it like a cj v8 swap. No more unobtainium plastic arms, heater cores or other bits.
its a 1997 and supposedly the Novak magic box is supposed to make the gauges work..LOL
I originally planned to get a hemi swap but that was way way way more expensive to pay someone else to install. Thats when I started researching TDI and 4bt swaps and found a place in Prescott, AZ that does them but after my quote they stopped responding to my text, emails and calls for over 2 weeks and that's when I started looking for another shop.
I think the shop gave me quote on that equipment and it was going to be like another $5k on top of what I had already paid.
I have a Novak RPM converter box for the stock dash and an LS motor for anyone that would like it. Free for members' only.
Novak was the company that supplied the shop with the trans, adapters and all the wiring and other stuff for install. What's stupid is the shop had never heard of Novak until I said something about them. So it makes you wonder what they would have done without Novak's help and parts?