black2000xj

i know the 1991 is a high output

there is a 1990 sitting at the end of a private cul-de-sac by my house

its in great shape (faded paint) but its very solid

its has a auto trans (aw4 i would guess)
and the 231 t-case

jeep has been sitting for months...they said the motor was making noise so they parked it.

now if its anything like my 91 it might be loud valve train or maybe the flexplate bolts

i really want this thing but i dont know about the motor if its decent or not

Radi

I believe '90 was the last year for Renix. You can tell pretty easily by whether it's a closed or open cooling system. There are other visible differences I'm sure, but I'm not that familiar with them where I can detail them.

There is nothing wrong with Renix, some members here seem to prefer them. It certainly is not a "bad" engine. I've never owned one personally, but wouldn't hesitate to buy one if it were a good deal.

arorton

I'm not positive, as I'm no expert on renix jeeps, but I thought the last year was 89.. Again not positive though.

black2000xj

how would i tell if it is a renix?

anyway by just popping the hood open?

i know it has the 4.0 emblem on the rear hatch...


owner says its a 1990...

looks identical to my old 91....right down to the interior colors

Lowrange2

Pop the hood. Does it have a radiator cap or not?

winston427

87-90 is the Renix. 91 was the first year for the H.O.

88jee

Last year is 1990. I love my renix, drives really good. Definitely have to see how many miles and such on it, maybe take a test drive to a trusted mechanic to try and diagonose the noise.

winston427

That's not always the best way to tell. A previous owner could have swapped the cooling system to the later style.

arorton

Isn't the best way to look for the plug to take care of the CEL? It's been a long day.. I can't remember what the little thing is called lol

black2000xj

i want to buy it but the owner just likes to leave it sit there

the only thing that worries me about the jeep is there is a jug of 50/50 in the back, and then they tell me its making a noise from the motor

Now it might not be anything big...but still....may have been overheated and ruined the motor...they just dumped coolant in to get home....


I will look into some more....maybe takes some pics and post them

XJ.89.Limited

Overheating could have happened. The cooling system on the renix engines isn't very efficient. I carry a jug of water everywhere I go just in case anything were to happen. A 1990 will have the renix engine, unless it was swapped. The cooling system can be used to determine it, but also look for the extra vacuum lines running everywhere. Look for the yellow connection ports under that black plastic shield that covers the coil. Follow the wire from the distributor cap back to the coil and you'll see them. Check underneath at the cat also. There should be no o2 sensors on the cat, only 1 right after the manifold on the downpipe. It's fairly easy to spot. Just follow the exhaust up to the engine while looking underneath. Also look for an obd port under the dash. There should be none. When starting it, it should take about 1-2 seconds longer than the H.O. does, so that would let you know also.

black2000xj

i will look at it tonight and report back!

88jee

Lol I carry a jug of 50/50 in the back of my jeep too. I was having some overheating issues when I first bought it so now its just a habit thing. I carry one in my other car too, just in case.

RTorrez1

I have always carried extra coolant in all my cars and truck and I have never over heated my XJ. Just a good habit for emergencies.

XJ.89.Limited

The yellow connectors should be on top of the black plastic shield, not underneath. Fail, haha. I hope you see this before you go look and get confused. Speaking of the cooling system, my upper radiator hose somehow was starting to come loose. I heard what sounded like a vacuum leak when I shut the engine off and then got really confused. Then I smelled antifreeze and popped the hood. Sure enough, it was dripping from where it connects to the radiator. Must've just happened too because nothing was slung onto the bottom of the hood from the fan. I pushed it back further, tightened the clamp, and it was fine. I could literally almost pull it off with the clamp still on there.