Buying a XJ tonight

Hello, well I'm taking the plunge... throwing a whopping $500 into a super clean, super stock 89 4-door XJ. Jeep doesn't run, been kept in a garage till about 6 months ago when the owner tried fixing it. He hasn't had any luck so I'm taking it off his hands, ODO has over 200k but he told me it was fully rebuilt at 160k and then he let it sit up for a couple years after getting a new truck... wish me luck, hopefully i won't have to pull the whole drivetrain out, but if thats what it needs then so be it! I'll be on here regularly gathering info from all of you.

My other Jeep is a Liberty :laugh: so this XJ; even though it doesn't run (at the moment) is a step up IMO.

Good luck and congrats!!! I hate the Liberty!

Welcome to the forum!

Once you get it in the garage, verify if it has spark at the plugs. That is job #1 for a no-start. Looking for a strong, blue, snapping spark. Orange/yellow/white spark indicates a weak spark, which may not be strong enough to start the engine.

If spark checks out, try spraying a small amount of starting fluid into the intake. If the engine starts and runs momentarily, you have verified a "fuel delivery" problem.

If it hasn't been run in 2 years, siphon all the old fuel out of there. Gas isn't that expensive and you want fresh fuel in there right out of the gate!

Good luck and keep us up to date!

If it was me I would also pull the plugs and put some sort of oil down in the cylinders to help lube them.

go1lum said:

If it was me I would also pull the plugs and put some sort of oil down in the cylinders to help lube them.

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A little Marvel Mystery Oil in the cylinders before you spin it over.

Good advice. Pull the plugs, shoot a little light oil into the cylinders, leave the plugs out.

Fully charge the battery and have it load tested--it is likely shot. The Renix 87-90 engine management system has to "spin up" the engine to 300+ RPMs before a strong enough signal is generated by the crank sensor (it is a signal generator) to get the ECU to trigger the ICM/coil for spark. Check those battery cables, clean both ends, replace the POS head to firewall braided ground strap with a 4 or 2 gauge cable--that is the ONLY unibody ground path, if it is hinky you will be chasing your tail on a lot of issues. Make sure all ground connections are stripped to bare metal, treated with an anti-corrosion agent, and make the connections tight. Don't forget the dipstick tube grounds--ECU, ICM, 02 sensor and others are attached there--very critical!

Crank the engine over without the plugs for a bit, then install the plugs.

Good luck.

Well good news, and more good news, hopefully... The XJ didn't have a battery *owners son pulled out the redtop that was in it* so after removing the driveshaft and tow-dolling it home I ran to the autoparts store for a cheap batt, came home and threw it in there. Didn't crank, but EVERYTHING worked! all the power windows, locks, lights, hell even the antenna popped up, factory radio turned on, got 1 blown speaker but thats a very easy fix.

The engine is not seized, since I was able to hand crank it a bit. There is some loose bolts on the rocker arm cover and some oil stains around it, but again another fairly easy fix. Gotta wait till friday to really dig into it, but I'm shooting to have it running by sunday. Going to stop by the parts store tomorrow when I'm at work and fluid up.

The old guys I bought it from son is a mechanic, and he advised me he "narrowed" the no start issue to the starter solenoid. The Cherokee Laredo has a newer starter, brand new water pump, injectors, distributor, wires & plugs, radiator, belt, and now a brand new battery... so I'll start lubing, and chasing grounds and really diggin into it on friday.

I assured my wife this wasn't going to throwing money into doing crazy modifications, and lifting it any time soon... but that 35 rearend has to go, might make a trip to the pick n pull this weekend too :shhh:

Oh man, I love a good hobby. We need pics, though.

Make sure you take a close look at your pos battery cable. My 90 threw me for a loop once when all the electronics worked but it wouldn't crank. Thought it was the starter when all it was was internal corrosion in the cable terminal. Built up enough resistance to not power a startup but the low power draw electronics worked. New cable fixed all my woes. It was gradually getting worse so a vehicle that's been sitting may be fully corroded

So as far as you know its a no-crank issue rather than a no-start issue.

Didn't see the transmission mentioned--if its an auto a primary suspect in no-crank situations is the NSS--neutral safety switch. You can confirm if it is the problem by jumping power from the main positive cable where it attaches at the starter to the solenoid positive connection--make sure its in PARK and the parking brake is set, ignition switch off. If it cranks the NSS is the likely culprit as it interrupts the ground circuit for the starter relay unless the trans is in PARK or NEUTRAL.

If it isn't the NSS it could be the ignition switch--not the key and lock cylinder--is not being properly positioned by the remote rod when the key is in the START position, so no power is going to the starter solenoid--silvery looking thing near the battery with one large lug (the Renix power distribution center) and three male spade connectors. Those spade connectors are IGN--12 volts from the ignition switch; SOL--when the relay is energized that spade connector sends power down to the solenoid to energize it; and GRND--the relay's ground.

Those NSS switches are SPENDY, that is the bad news. The good news is you can remove it, clean it, lube it up with dielectric grease, reinstall and adjust it for a little sweat equity and the cost of the grease.

Good luck with your XJ. I also purchased an '89 XJ (4.0 I6 A/T) last December. Mine was running though. I got it pretty reasonably from a small dealer. He was eager to dump it because it had a wicked high idle (a common Renix issue) and some oil leaks. Everything worked, including the A/C and the interior was mint. Fast forward to today. I put some money into the XJ over the summer. The cooling system is completely replaced (with the exception of the heater core but I inspected it). I replaced some gaskets and gave it a complete tune-up including some sensors. The XJ is in excellent condition with 190,000 miles (I got it with 178,000). I put some nice Bridgestone AT tires on it and a new stereo. I really like the Selec-Trac four wheel drive. Having a choice between full-time and part-time 4X4 is handy. Hope you enjoy the XJ.:clap:

Well its not a no crank or no start problem yet, just a "i like to touch all the bases before heading home" issue, im sure i could spend a couple hours n get it running, but i want it to be ready to run. I really appeciate the advice, i got a good idea where to start now when i tear into it on friday.

It has 203k on the straight 6, aw4, np 231 i have the selec-trac in my kj it works alright but i had an issue with it sticking in 4 high a while ago.

Alright worked on the jeep last night till 1am! Pulled the plugs, they looked used but in good condition, drained the oil it was very dark, but not milky, removed the airbox, filter and corresponding equipment to be cleaned. Throttle body is clean looking, filled the jeep up with oil/marvel and put some cheap plugs in for now, going to take them back off tonight and put a little bit more oil in the cylinders. Drained the gas and put 5 gal of plus in it with some seafoam. Took the starter off and had it tested and it was bad! So got a new one, so far im up too $675 in including the price of the vehicle, after all the fluids maybe another couple parts ill prob be around 8-900 not bad for a cherokee! I've got a 2k budget on this from the wifey so maybe ill throw a CAI, header & exhaust on it too! ill try to get some pics up asap.

RamlebXJ said:

Alright worked on the jeep last night till 1am! Pulled the plugs, they looked used but in good condition, drained the oil it was very dark, but not milky, removed the airbox, filter and corresponding equipment to be cleaned. Throttle body is clean looking, filled the jeep up with oil/marvel and put some cheap plugs in for now, going to take them back off tonight and put a little bit more oil in the cylinders. Drained the gas and put 5 gal of plus in it with some seafoam. Took the starter off and had it tested and it was bad! So got a new one, so far im up too $675 in including the price of the vehicle, after all the fluids maybe another couple parts ill prob be around 8-900 not bad for a cherokee! I've got a 2k budget on this from the wifey so maybe ill throw a CAI, header & exhaust on it too! ill try to get some pics up asap.

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Just couldn't wait till Friday could you!
Sounds familiar.
Good luck and keep posting!

Ha... Yea i got my 3 year old that goes to bed at 7, and my pregnant wife hits the hay around 8, im a bit of a night person so after they go to sleep im outside wrenching on something

:flamemad: ha... alright replaced the starter, gave the engine bay a once over with some electric cleaner/brake cleaner/degreaser, tried to clean it up as much as I could. Went to crank it up... Nothing! yea... kinda sucked was really excited to hear it fire up. Checked the grounds, cleaned them up a bit, still nothing. I'm going to replace the battery cables, they're not that bad but better safe than sorry. I'm also going to swith the firewall ground to 2 guage wire instead of that flimsy thing that was installed.

I hooked even hooked the kee starter up to the Optima on my Liberty to make sure it wasnt a ground or power issue, still nothing. SO I'm assuming now that is the neutral safety switch, gotta wait till friday to buy some parts now :smoker:

I know this technique is a little risky but try this: SO USE CAUTION WHEN ATTEMPTING

With your foot on the brake....turn the key with your left hand and hold in the start position, with your right hand move the shifter from park to the other gears slowly.

You might notice it will try to start somewheres (usually around the neutral spot) in the travel of the shifter.

When my NSS was bad...it had a sweet spot where it would start.

This would confirm your problem is your NSS.

I'll give that a try tonight, still got a bunch of cleaning to do and need to replace the valve cover gasket. Might wait till tomorrow though, hell even after I get it running I need to flush the coolant, oil in the diffs, tranny oil, trans case, and new oil in the engine & new plugs after I let it run for a few hours. Going to be a fun weekend!

Well, she cranks... hooked up the new ground wires, and batt. cables, got in to crank it over and it doesn't seem like its getting gas... well I figured out the reason! This was shooting fuel off about 3' in the air from where that part connects to the fuel rail. Now I'm not the most up to date on the 4.0, but that looks like a pressure regulator? now the question, is this a part I can pull off and put a new one on there? maybe a o-ring? or is it attached & i'll have to buy a whole new fuel rail?

Good news is I know the fuel pump is working! and I'm still under $700 total invested!

There is an o-ring between the FPR and the rail, but it's also possible the FPR itslef has gone south. Easy enough to change the o-ring though. The o-ring is often included in the injector o-ring kit.