Eagle

Yep. You have to get a cluster that fits your year, though. They used mechanical speedometers from 1984 (Cherokee) through 1990, and electronic speedoometers from 1991 up. There were two types of the mechanical speedo, and they don't interchange. The early type ran from 1984 through either 1986 or maybe mid-1987, the new type from 1987 through 1990. Also, if possible get a tach out of a vehicle with the same number of cylinders you have. Some of the tachs have a potentiometer and can be adjusted for four or six-cylinder use ... but not all have that.

U.S. Army, Vietnam veteran. Started off as a combat engineer (I think that was 12B), then after I got to 'Nam they didn't know what to do with me so I spent the last part of my tour in 4th Infantry Division HQ. I think they reclassified me 71H. I made SPC5 about 6 months before my ETS.

A '69 Wagoneer has 6-bolt wheels, doesn't it? You're going to need custom-made axle shafts no matter what you do for brakes, unless you swap in a matching 6-bolt front axle.

I wasn't suggesting that you buy a kit. I was suggesting that by buying the '91 Cherokee you are getting the kit, "on the hoof." You should not need to swap in the interior harness unless you really have your heart set on tearing out the dashboard and then reinstalling it. My whole point in mentioning the Mopar kit was to show that the engine controls can used used stand-alone.

As Pete said, they are totally different. The 89 has a Renix ignition/injection, the '91 is a Mopar. The 89 has a mechanical speedo, the 91 has an electronic speedo. The good news is that I believe the engine controls from the 91 can be used stand-alone. Jeep used to sell (and maybe still does) a MPFI conversion kit for the older 4.2L Wranglers that originally had a carburetor. The conversion is basically the entire MPFI setup for a '94 Wranger 4.0L. If it can be retrofitted to an older, carburetted vehicle, I can't see any reason why you can't drop in the motor and assciated controls without rewiring the dashboard and chassis.

Clogged catalytic converter, maybe? Bad oxygen sensor? The O2 sensor isn't used during warm-up, when the engine runs in open loop mode. The ECU uses input from several of the sesnors only after things reach normal operating temperature and switches over to closed loop mode operation.

Good question. I wish I had a good answer ... but I don't. I've never even considered it.

Thanks, CW. Man, the rest of you dudes make me feel OLD. I came back from Vietnam in 1968. Looking at these other terms of service, I get the feeling most of you weren't even born then. Where's my walker?

"Intimidation" should not be a consideration. The bottom line is, you should NOT be opening the door to a stranger at 3:00 a.m. Period. Not even if it's an innocent-sounding female voice. Scum bags have girl friends, too, and they have been known to use same as decoys. If someone says they need help, ask them who they want YOU to call and what the number is or, better yet, just tell them you'll be happy to call the police for assistance and see what happens. To hell with intimidation. Don't open the door. The gun is for shooting someone who tries to break through the door, not for posturing after you've let the scumbag in.

Once the cables get rusty, you can't bring 'em back. They're $17 from Advanced Auto (a.k.a. Shucks or Kragan in some parts of the country). Just replace them. I'm on my way to pick one up at my local Advanced emprium in a few minutes.

Some '87s were retrofitted with a ballast resistor under a factory TSB. It was not standard from the factory on 1987 models. I keep it in my '88s, too, but not because I fear any problems from NOT having it. I also have an '87 MJ and that's been chugging along fine without it. I keep it because part of me is of a collector/restorer/purist mindset, and I prefer not to remove parts the factory put there just in case I enter one of the trucks in an AMC Owners Group show. You won't hurt anything by bypassing it, and you won't hurt anything by replacing it. If you replace it -- buy two and keep a spare in the glove box. That's pretty much S.O.P. for any vehicle with a ballast resistor. Chrysler was notorious for using them in their ignitions and having owners get stranded as a result.

www.car-part.com

Nope. It is there for a reason. The 87s (XJs and MJs did NOT have it, and people complained that the fuel pump was making too much noise. So for 1988 they added the ballast resistor to reduce the voltage to the fuel pump, which makes it run slower, which makes less noise. The fuel pump and regulator are exactly the same for an '87 and an '88. You will NOT damage anything by soldering those two wires together.

This is for a 4.0 is it the same as 2.5? For 1988, yes. Your TBI is still a Renix system, same as the 4.0L. Most of the sensors are the same. I know the CPS is the same part number.

Always look for the obvious. Coils and ignition modules do go bad ... but very rarely, and virtually never right on cue after you did work unrelated to them. So I suggest you stop looking in that direction and be open to the very real probability that, regardless of what you THINK you didn't mess with -- somewhere in the process of changing the valve cover you disconnected something related to the spark. My guess is the CPS. The wire runs right behind the back of the head and valve cover. There's supposed to be a clip back there -- I don't know if that clip is attached to a valve cover bolt on the 2.5L. Are you certain you didn't disturb the CPS wire or connector? Keep in mind that you may not have had to unplug it -- it runs near the exhaust manifold, and if your wire was even damaged, it could have worked but then jostling it when you changed the valve cover might have shorted it out. There is a way to test the CPS with a multi-meter. Somebody posted a link awhile back to an article by a guy with screen name Jabba the Hut who posted a description of how to test all the sensors in the Renix system. See if you can find that article. Does anyone have it book-marked?

Sounds like the clutch release bearing ("throw-out bearing") is gone. For an '88 4.0L, unfortunately that's all one assembly with the slave cylinder, so the part is pricey, but (subject to verification) I'd make that the first thing to have checked out. If you get confirmation that's the problem ... DO NOT give in to the temptation to save $$$ and buy the part from any after-market source. Replacing the release bearing on a 4x4 is not an easy or inexpensive job. You do NOT want to repeat in 6 months, and that's about the average lifespan for aftermarket clutch hydraulic system parts.

I don't know where you live, but opening the door was NOT a good idea. Yes, you armed yourself ... with a knife ... but the first rule of gunfighting is "Bring a gun." (Or "Don't bring a knife to a gunfight.") There have been several ARMED home invasions around here in recent weeks, and the invaders were armed with guns. If you had opened the door on a home invader rather than a drunken undergrad, he/they would have seen the knife and shot you on the spot. Do NOT open your door to unknown parties pounding on it at 3:00 a.m. Talk to them through the door if you wish (standing well to the side where they can't see you and hopefully can't shoot you through the door) or, better, just call the cops and tell them it sounds like someone is trying to break in your front door.

I bought a replacement gasket from the dealership a couple of years back, so losing the gasket is not my issue. I just couldn't figure out how to uninstall the window from an existing truck.

CPS. Yes, the TBI 4-cyl uses the same CPS as the 4.0L, and it causes the same problems when it goes bad.

Do you remove it from the inside or the outside? If this is something I can do at home, I have a pair of MJs waiting to have the sliding window moved from A to B, and vice versa. I even had a professional auto glass guy look at them, and he couldn't tell me how to do it.

Well, you guys made me go out and get dirty. It isn't often you whippersnappers get me doubting what I know I know, but my worthy opponent with his videos (which I can't see -- I'm on a dial-up) left me wondering. My '88 MJ doesn't have the original tranny or transfer case, so that would not have been a fair test. My '88 XJ, however, I bought new ... so I know it has the original tranny and the original transfer case. So I went out this afternoon, put the transfer case in neutral, put the transmission in first gear, jacked up the rear wheels and tried to turn them. Verified: The front and rear driveshafts ARE locked together. Further, this exercise reminded me that the ONLY way to get the transfer case from 2-Hi to Neutral is by first going to 4-Hi -- and that engages the front axle disconnect. This is why the owners manual says to tow it with the wheels off the ground, or else flat tow it with all four wheels ON the ground. Now -- why the discrepancy? I don't think Lead_Not_Follow is deliberately trying to mislead us. Since I can't view the videos, I don't know which of his three vehicles he used for the test ... nor do I know if any of his three is in factory configuration. But I do know that the XJ I just looked at is in factory configuration. In one of my initial posts in this thread, I said that I believe Chrysler changed the 231 so that Neutral does not lock the two driveshafts. I thought that happened around '93 or '94, but in thinking about it, it makes more sense that they would have done so in 1991 -- the year they stopped using the front axle disconnect. So my guess is that L_N_F was not looking at an '88 transfer case. But the guy asking the question has an '88. Which points up the fact that Jeeps are NOT all the same, not even within the relatively short span of the MJ, and it's never safe to generalize that what works for me MUST work for everyone. I stand by my opinion that you cannot tow an '88 on a dolly with the transfer case in Neutral. You could leave it in 2WD, but that would probably chew up some bearings. The safest course is still to remove the rear driveshaft and cap the transfer case tailshaft with a cut-off soda bottle.

Dunno if this is what you meant to write. Every OEM Cherokee/Comanche radiator I've seen had plastic tanks, and both replacements I bought had metal. The guy at the radiator shop said he can't work on the factory rads because he can't fix the plastc tanks where they meet the metal core.

If you have the MPFI computer and harness, I would update the 'Manche to the newer system. You'll get more power and better economy. Here's the deal: After Jeep introduced the MPFI 4.0L, a lot of people with the older, carbureted 4.2L engine in their YJ Wranglers were feeling left out. So Jeep came up with a kit to convert the carbed 4.2L Wranglers to MPFI. Basically, the kit is "just" the manifolds, injection, ignition, ECU, and engine room harness from a '94 Wranger. So ... if Jeep could split the system up to use just the engine controls to convert the older Wranglers, I see no reason why you can't swap in an engine that's already set up for it and just use the engine harness from the Wrangler in your MJ. Your speedo is mechanical and has NOTHING to do with the engine controls, so don't worry about it.

Correct

How much time before it goes loco? Initial guess --> oxygen sensor bad. Explanation: On a cold start, the engine by-passes most sensors and runs in "open loop mode," in which it pretty much ignores sensor inputs and uses a pre-programmed, slightly rich fuel map to run. Once the temp sensor sees that the engine is up to the operating range (around 180 degrees, minimum) it switches to "closed loop mode" operation, in which it reads the O2 sensor, temp sensor, MAP sensor, TPS, etc and controls the fuel mix and ignition timing accordingly. If it runs okay cold but goes wacky once it gets into closed loop mode, there's likely a bad sensor. The task then is to identify which one.