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Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!ZJ (93-98), WJ (99-04), WK (05+)
All ZJ/WJ/WK specific tech questions asked here!
My kid and I have a 94 ZJ we've been cocking around with for years (since around 2004), and it's finally reached the point where we've decided to go FULL TILT BOOGIE on this beotch It's already lifted, reinforced, chopped, hacked, and butchered, lol.
I'm gonna start a Build thread as well, but for right now we need some advice: We are gonna gut this electrically, and put in an aftermarket ignition/fuel controller, as well as whatever else we need to do for bare-bones control functions. There will be a fuel cell with pump, interior battery, etc. Basically an off-road race setup, roll cage, seats, etc.
We Don't Care about ABS, seat belts, lights, airbags, trans shifting, this sensor, that sensor, etc. The PCU is coming out, all I'm gonna save is the main fuse block, etc. This is strictly a mud/hill machine that will never see a road again, and may never even get shifted into D, and we can handle all that with the shifter.
As far as I know, all we really need is Ignition/starting & fuel/injector controls, and Alternator/Charging systems. My concerns are steering & braking, as they are both power, and I think we need to keep them live. 4WD also, I haven't figured out how to maintain the interconnect for that yet.
Anyone ever gone this far with a Jeep before? I've done it several times with older carburated machines like Fords & Chevy trucks, but never with something that was manufactured with all the power accessories and what-not like this critter.
Any advice on where to look for parts & tech support?
IDK if your 94 has the 42re trans or not, but if so, dump it for the AW4 from an XJ. Also use the NP231 t/case and an externally controlled alternator, probably around 175 amps for lights. For low speed running or rock crawling, use an electric fan or 2 with a separate trans cooler. The 4wd takes care of itself, being that it's all mechanical. The power steering and brakes should be no problem either. Use what you've got.
You're going to need some kind of electronic engine control for the ignition and fuel injectors, plus the intake sensors for fuel trim. IAT, IAC, MAP, and TPS.
Check with the "modified cherokee tech" section.
Last edited by dave1123; Dec 12, 2016 at 09:19 AM.
Yeah, in 67,all we had for emission controls was a PCV valve! 68 had air injectors in the exhaust ports and 69 had catalytic converters and EGR valves. Fuel injection required lots of electronics to get it to be efficient, of course there was the Rochester mechanical injection system of the 64 Corvette, but everyone I knew that had one wound up with a Holley 4 bbl carb on it. Yes, I know Bendix and Chrysler monkeyed with an electronic system in 57, but they didn't work out either. Benz developed the basic electronic system for their diesel cars that eventually wound up on gas cars.
Actually, take a look at the fuel injection systems on F1 cars! Now there's a complicated system!
Last edited by dave1123; Dec 29, 2016 at 06:48 PM.
You're gonna create a whole bunch of headaches by ditching the factory wiring harness. Thirty years ago you wouldn't have much of a problem, but your 94 uses a lot of electronics for even the simplest of circuits. Good luck.
My brother has a good one; "The most complicated and least reliable software is the guy behind the wheel!" That said, I don't think I'll ever trust an auto-drive vehicle with my life. You kids have a good time now because in 30 years, you won't be allowed to drive a manually operated car on public roads. JMHO.