found me an xj but its got problems please help

Hello to all. I have finally found me an xj after several years of looking for just the right one. Its a 1990 model 2door 4.0 5speed. With 150,000 miles on it. The ole thing looks great no rust and only one bad dent. But it has a few querks i would like to ask the experts about. The guy at the car lot says the rear main seal leaks. i read the post on how to replace it but i just dont have time to do that. Could anyone tell me the average price to have that fixed. Also the thing idles high all the time between 1800-2000 rpm. it never did drop below that while i was test driving it. it looked like the valve cover was leaking some oil aswell but there is definatly oil coming fron the rear o the engine running down the transmission and driping on the ground. also is the 5 speed in this xj one of the stronger ones i have a magazine hear at home that says the 90 models has what they call a "puke-a-lot" transmission in it but according to this site that trany was droped in 89. any input on this would be a big help in my decision to buy this jeep or pass on it. thanks alot ohh and one more thing what type of gas millage should i expect to see since it will be a work vehicle.

My XJ is 2000 but I'm positive the rear main seal is a problem with all XJs... But almost everyone doesn't replace them immediately. Just keep oil in it and it will keep going. As for dripping oil down below the tranny, mine does that too, but I haven't had any problems.

My 2 cents: a 2 door = pass, a 5 spd = pass unless you are a really good 4 wheeler, leaks oil to point of dripping = pass, unexplained high idle = pass. Unless you want to spend a lot of time and/or money on this; I say pass. Chuck

Rear main seal does leak on some, none of the 4 I had ever leaked, one with as high as 180,000, depends on the conditions in which their driven

the seal itself isn't expensive but the labor to replace it will take a nice chunk of your bank account, since you said the valve cover gasket is leaking it's possible that the oil is just dripping down the back and making it look like the rear main is leaking, when I bought my 97 the guy said the rear main leaked, it turned out to be just a transmission cooler line

As for gas mileage depending on how heavy your foot is you should get between 17-20 mpg's around town and a little over 20 on the highway

I don't know if has the "puke-goat" BA-10 or the AX-15 but if your going to wheel it you want the AX-15. If your going to keep it stock the BA-10 should hold up, being a 1990 it is a Renix, do a search on that, there is a neverending debate around here on which is better, the Renix or the HO's

IMO starting off with one rust free is the way to go, depending on how your going to drive it will depend on if that one is right for you

Since you seem to have been searching for a while make sure this IS the right one, there is a ton of XJ's out there

BTW how much would you be paying for this XJ, that could be another huge factor, if the price is right...

ok thats about what i figured id do was ride it with the oil leak it didnt look to bad he said it hadnt been moved in a week and the oil spot was just about as big as my fist so im not to conserned about that. as for the high ideling that was my main consern. im stupid when it comes to workin on cars with efi. i can do the whole lets put on a lift cut the finders and tear out the rear end all in the same weekend thing but i dotn do motors.

chuck a 2 door and a five speed is just what i have been lookin for i have found several 4 door autos but i dont want a 4 door at all. i can deal with the auto but i prefer a 5 speed. this will just be a trail rig it will be my work truck. so easy to drive on the trail vs a few more mpgs the mpgs will win every time.

How Much?

I like the 2 door as well, its what I got and it was what I was looking for. I'm sure at one point or another the doors will sag and cause me problems and its not too easy for people to get into the back. good thing i dont have many friends. But like I said, I like it. And 5 speed, I like it.

rear seal ...welcome to the club .....all 4.0L leak at the front and rear seal ...high idle ...TPS sensor is toast....or vacuum leak ....Im on my 2nd TPS sensor in 3 months.....Im sure Im not the only Jeep owner with this problem!! carry a spare TPS ...

Rear Main Seal is a common problem. My mechanic said about $200 to repleace. He suggested that as long as I keep a watch on it just to let it leak until you have to replace something more major. I paid about $125 to replace the valve cover but had some other work done at the same time so I don't know how much of that was just for the valve cover. I think the gasket was about $50. There is a cheaper one but go for the rubber seal.

gomerkfx700 said:

Hello to all. I have finally found me an xj after several years of looking for just the right one. Its a 1990 model 2door 4.0 5speed. With 150,000 miles on it. The ole thing looks great no rust and only one bad dent. But it has a few querks i would like to ask the experts about. The guy at the car lot says the rear main seal leaks. i read the post on how to replace it but i just dont have time to do that. Could anyone tell me the average price to have that fixed. Also the thing idles high all the time between 1800-2000 rpm. it never did drop below that while i was test driving it. it looked like the valve cover was leaking some oil aswell but there is definatly oil coming fron the rear o the engine running down the transmission and driping on the ground. also is the 5 speed in this xj one of the stronger ones i have a magazine hear at home that says the 90 models has what they call a "puke-a-lot" transmission in it but according to this site that trany was droped in 89. any input on this would be a big help in my decision to buy this jeep or pass on it. thanks alot ohh and one more thing what type of gas millage should i expect to see since it will be a work vehicle.

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If it has been setting up a while (Many Months), driving it will help slow the rear seal leak. Also some aftermarket oil sealer additives might buy you some time. Avoid all synthetic oils until you replace all the orings, gaskets and seals all over the engine. Use dyno oil only! Synthetic will turn a small oil seal leak into an oil gusher!

Replace the valve cover gasket, clean the CCV tubing system attached to the valve cover and fix any vacuum leaks in it, locate and fix any other vacuum leaks, pull and clean all the ground wires, 5 major locations under the hood for the ground wires, and not real hard to do (all this will help reduce the high idle), then recalibrate (simple digital multi meter & mouniting screw adjustment) the TPS (Throttle Position Sensor) and your high idle should be gone. If not a few other low cost parts, like the TPS and MAT sensors might be bad, but do the other stuff first. The TPS and MAT sensors can be tested with a $10 digital multi meter!

How much are they asking?

How does the engine sound?

I have seen jeeps like that go for $500 to $2500, depending on the location and situation. I would not pay more than $2,500 for it, and probably buy it as is where is (if I was shopping) if it was $1,500 or less. I just paid $450 for an 87 with no engine, tranny, or radiator. In fact nearly everthing under the hood had been stripped already. The body and interior are real nice, low milage. Got the entire rear end, steering column, front end and gear box, drive shaft (2WD) and nice tires and alloy wheels in the deal. The engine had blown due to a large oil leak the prior owner missedjudged.

1600 for the 2door. the way it is i also found another one yesterday man it must be jeep days hear or something they are poping up everywere. its a 94 model 4door 4.0 h.o. 5 speed dont know much about it besides that i didnt get to talk to anyone. the lot was closed. im goin to cheak on it monday.

seems like every leak on the 4.0 looks like a rear main. Valve cover, oil filter adapter, rear main all drain back to the same spot...it seems like. Alway ask if its ok to have it checked out by a reputable(not someone they suggest) mechanic(look for a clean shop, not a lot of junk sitting around, not a chain store either)...be there to crank it up cold in the morning (be the first one to turn it over that day)...use special problems for barganing but dont bring up regular wear issues...they dont want to hear that the suspension bushings are worn on a 15 yearf old jeep..duh...its 15 years old. Dive under and look for rust issues too...rockers, above muffler, rear bumper mounts

Don't depend on great miliage until you do some work on it. Expect 10-12 mpg avg at first on the 1990, especially while working on the idle problem. Also an old O2 sensor (versus a new one) will cut the mileage nearly in half, so plan on a new O2 sensor right away if the mileage is below 14-18 mpg city/highway.

Also check it for overheating (radiator-fan-clutch...thermo), run it drive it for a god 10-15 minutes if you can before deciding what it is worth.

1990 is a Renix 4.0 , I have never gotten over 18 mpg highway, 15 mpg avg and 13 mpg city (lots of stop and go) since I bought and started working on my 87 Renix 2.5 years ago.

The new O2 sensor and ground repairs did the trick on mine. But it took me 2 years to figure that out.

thanks allot everybody is there any real pros to the 94 model i found other than the ho engine over the 90 model any tranny or tcase changes or is everything else the same. im really tryin to weigh this thing out i can go for the 4 door just to get the better engine if the price is right. especially if it dont need any work done to it.