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Unread 12-28-2012, 04:47 PM   #1
bird6246
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1997 TJ Wrangler 
 
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2.5l tj swap to a 4.0l xj HELP

Just bought a 97 TJ with a blown 2.5l not a big deal was going to do a swap. Have done a lot of different research, have checked literally 100's of different articles. but i can't find a definitive answer to my question.
Question is
I have acess to a complete 91 xj 4.0 auto. will this work in my 97 tj. Confused about the obd1 versuses obd2, whether or not the guages will work.
Any help, tips, advice would be greatly appreciated.

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Unread 12-28-2012, 06:56 PM   #2
ratmonkey
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the mechanicals can work, but you need the obdii computer and wiring to work with the tj gauges.
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Unread 12-29-2012, 06:03 AM   #3
bird6246
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so what would it take to get the obd2 computer to work. Is that where you wire in 2 more injectors? Do i need a 4.0 harness and ECM from an obd2. I was going to swap whole driveline and use auto trans and t/c. Are they computer controlled.
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Unread 12-29-2012, 09:29 AM   #4
leftlanetruckin
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For someone that has read and read, you didnt absorb much by the sound of it!
You need the whole harness for OBDII operation, thus a donor from the OBDII years would be much better. The "adding 2 wires for the 2 extra injectors" trick is possible when you are reusing the original wiring harness. Good for a 2.5 manual to 4.0 manual swap etc.
The transfer case is manual control only, with a few sensors to tell the rig to light the low range lamp, and a VSS. The AW4 is a computer controlled transmission, thus the TCU behind the dash on most XJ's.
You would probably be better reading up in the yj section, as there are MANY swap threads there. Never really bothered with the TJ section myself, didnt like the vibe there when I last visited.

Martin
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1998 XJ on 37's.JK Rubi axles with chromo shafts and ctm's, 4:1 transfer case, etc etc etc.The Cherylkee....
2003 Range Rover HSE, 4.4 Quad Cam.
1998 Range Rover 4.6 HSE
2000 4.7 4WD WJ with a rebuilt motor.
4.3/700r4/new frame buildup (YJ)....
http://www.jeepforum.com/forum/f12/swap-offically-underway-324622/

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Unread 12-29-2012, 10:52 AM   #5
ratmonkey
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your best bet is to find a 1996-1999 donor xj or tj depending upon if you want the aw4 automatic or if you would rather go manual.
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'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.

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Unread 12-29-2012, 01:24 PM   #6
bird6246
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checked around some more was able to locate a 96 xj drivetrain, no computer or harness though. should be able to locate those in the local scrap yard. Thanks for the help.
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Unread 12-29-2012, 02:29 PM   #7
leftlanetruckin
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If it has all sensors and manifolds, you should be able to get your harness to work. Just be sure to get a matching ecm for whatever tranny you end up with.

Martin
__________________
1998 XJ on 37's.JK Rubi axles with chromo shafts and ctm's, 4:1 transfer case, etc etc etc.The Cherylkee....
2003 Range Rover HSE, 4.4 Quad Cam.
1998 Range Rover 4.6 HSE
2000 4.7 4WD WJ with a rebuilt motor.
4.3/700r4/new frame buildup (YJ)....
http://www.jeepforum.com/forum/showthread.php?t=324622

Years to gain the hands on experience, and offer it freely.
Minutes to gain the knowledge from the internet, and quote it just as freely.
Choose wisely!
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