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newbie help....please??

RaccoonJoe

NAXJA Forum User
Location
Fort Wayne, IN
I just purchased an 89 XJ Limited, with the 4.0L and the auto tranny. It's been around the block a few times (212K miles), but still seems to run strong. I've got a few questions about it, tho....

I drive an average of ~600 miles per week, so this XJ is going to mostly a road vehicle...with the 4WD coming into play on some of the county roads out here, or if I have to make a pit stop in a cornfield somewhere :shhh:

Here come the questions:

As far as I know, the XJ was driven daily by an old, handicapped man since it was new. He sold it to my buddy, whose wife drove it for 5k miles before deciding she didn't like the MPG. Then it sat around for 3-5 months, getting run just long enough to make it across the driveway once in a great while. What should I be looking for, preventive maintenance wise??

I've put about 200 miles on it so far, and just at a rough guess (without a calculator), I'm getting about 15 MPG (60% highway, 40% city) Anything I can do to improve this??

I've noticed 2 other potential problems.....I have a real bad fuel smell when starting it in the morning, like it's running *really* rich. I also have an incredibly low idle when sitting in gear at a stop light. (low as in 200-300 RPM, Jeep starts to shake and rattle, feels like it's trying to stall, etc....)

So far.....
Repairs Needed:
Oil Change
Seafoam in the vacuum lines (should I do this?? why or why not??)
Spark plugs/wires
Distributor cap/rotors
Track down and fix neg. battery cable/grounding strap issues

Repairs done:
Seafoam into new tank of fuel
 
O-rings

The gas smell is probably the o-rings in the injectors. Easy fix under $100 if you have it done. The mileage is about average for an XJ. You can get a freeflow exhaust and air filtration to boost it a little.
 
if its running really rich, that might be the O2 sensor....
low idle could be the idle air control valve...

Seafoam the intake or the vac lines before you replace your O2 sensor

I'd also make sure you change the diff fluid, TC fluid and maybe flush the tranny, especially if you have some rough shifting

Oil change, plugs, wires, O2 sensor, IACV can/will help your MPG
 
Till this day i cant get rid of the raw fuel smell that comes out of my exhaust every morning.
I have tried replacing many things o2 sensor, map, tps, iac, orings, fuel injectors and till this day i still cant find out why in the morning it smells so damn rich, pretty bad honestly- Other wise the jeep runs strong and fine, my gas mileage might be a bit low.
If you come by a solution or anyone has a suggestion please by all means let me know as well as the original poster.

pete
 
RaccoonJoe said:
I just purchased an 89 XJ Limited, with the 4.0L and the auto tranny. It's been around the block a few times (212K miles), but still seems to run strong. I've got a few questions about it, tho....

I drive an average of ~600 miles per week, so this XJ is going to mostly a road vehicle...with the 4WD coming into play on some of the county roads out here, or if I have to make a pit stop in a cornfield somewhere :shhh:

Here come the questions:

As far as I know, the XJ was driven daily by an old, handicapped man since it was new. He sold it to my buddy, whose wife drove it for 5k miles before deciding she didn't like the MPG. Then it sat around for 3-5 months, getting run just long enough to make it across the driveway once in a great while. What should I be looking for, preventive maintenance wise??

I've put about 200 miles on it so far, and just at a rough guess (without a calculator), I'm getting about 15 MPG (60% highway, 40% city) Anything I can do to improve this??

I've noticed 2 other potential problems.....I have a real bad fuel smell when starting it in the morning, like it's running *really* rich. I also have an incredibly low idle when sitting in gear at a stop light. (low as in 200-300 RPM, Jeep starts to shake and rattle, feels like it's trying to stall, etc....)

So far.....
Repairs Needed:
Oil Change
Seafoam in the vacuum lines (should I do this?? why or why not??)
Spark plugs/wires
Distributor cap/rotors
Track down and fix neg. battery cable/grounding strap issues

Repairs done:
Seafoam into new tank of fuel

First off it sounds like you have a good plan, I would stick with it see how that goes. If getting 15 mpg already don't mess with the O2 sensor. Definately work on all those items including the ground. Once you are done with them all, recalibrate the TPS sensor on the throttle body to 0.82 volts at idle, with power on, engine off, using pin B to pin C with the TPS still connected to the wiring harness. You will need to back probe the connector to get the measurements. Loosen the tie down torqs screws and rotate the TPS sensor until you have 0.82 volts than tighten it down so it reads 0.82 volts at idle (engine off, power on). Then start, run for 3 mniutes, stop, off for 60 seconds, then repeat it 2 more times and let us know what the idle speed is then, both cold and hot! The repeated strating ans stopping is to give the cpmputer time to go through a complete cycle to replace old table data it stores and uses. 3 times seems to do the trick with the pre 91, Renix systems.

I would get all that done first, then check city/hyw mileage report back here as to results, and then get a fresh to do list if you are still having any problems.

You can also pull and gently clean and reoil the IAC motor, but read up on it in some old threads here first, as they are delicate!

Oh,

And the raw gas smell at start up may just be the system (O2 sensor and Cat converter) warming up. How long does the exhaust continue to smell at the exhaust pipe exit?

It could also be a leaking fuel injector that dribbles some fuel after the engine is turned off. That fuel would be blown out the exhaust at start up. If that is the case (and you can pull and test them) you might want to replace that injector, or all of them. Cleaning the injectors (fuel additive like seafoam might unstick it or them).

Does it smell at start up with a hot engine, after sitting for 10 minutes????? If so I would suspect a leaking fuel injector. You did say the smell is coming from the exhaust, right?, Not from under the hood????
 
@ EcoMike
The fuel smell doesn't come from just the exhaust, or from under the hood. Honestly, I cut my schedule pretty close in the mornings....start the Jeep, then put the dog in the kennel, then it's time to roll. When I'm sitting in the Jeep, (driver's door open) right after starting, and while cranking is usually when I smell it. When leaving the office in the afternoon, I don't smell it as much.....maybe because the windows are open?? IDK....never stuck my head into the exhaust stream to take a good whiff

@JNickel101
I was told that the "4WD system was checked/inspected" before I purchased it....when my buddy's wife started driving it. It was wintertime, he didn't want her to be stranded in a snowdrift without the 4WD (to get herself stuck even worse)

I've played with the Jeep a little bit in the yard/parking lot, just making sure that it shifts into 4HI and 4LO, and it seems to work without any problems. On the other hand.....during daily driver duties, I've noticed that it seems to slip quite a bit when shifting into OD (I can actually watch the tach jump ~200 RPM, and feel/hear it slip). Other than that, she runs like a champ...Just need to keep it in 3 when driving around town so it doesn't keep shifting between 3rd and OD.




Keep the ideas coming, this is all good stuff for me. I know there's a ton of info out here....
 
The raw fuel smell could also be leaking injectors, if they're still original. It's a possibility - RENIX fuel injectors typically start leaking at the body crimp around 150-180Kmiles, but some have gone longer (longest set I've heard of was 225Kmiles - on my 88.) Check the injectors at the body crimp seam, just below the electrical connector. If it's wet there, don't drive it until you replace the injectors - engine fires suck!

You can use SBFord injectors, and FiveOMotorsports (www.fiveomotorsport.com, I think) gets about $200 for a set of six reconned pulls - which is way better than $60 a throw for new aftermarket replacements!

If you've a fuel leak to correct, it can play Hob with your fuel economy - so check everything. Also take a good look at the fuel pressure regulator at the front end of the fuel rail - it's sealed in with a fuel injector o-ring (same as the other dozen you've already got,) and it may be leaking.

If it's sat for a good long while, I'd keep an eye on the following:
Valve Cover Gasket
Oil Sump Pan Gasket
Crankshaft Front Main Seal
Crankshaft Rear Main Seal
Timing Chain Cover Gasket
Oil Filter Adapter O-Rings
Fuel Rail O-Rings
Fuel Line "quick-connects" (you can get a kit to renew this seal, and it should be done each time you pull the connector apart anyhow.)
Transmission Cooler Line "quick-connects" (if you have the four-speed auto. Two on the pax side of the transmission case, one on the lower cooler line. You can get a kit for these as well.)
Any other gasket that isn't constantly wet.

A lot of times, gaskets can dry out and shrink if the engine isn't run, say, at least once a week - and that shrinkage will cause a leak. Replacement is the only option for this. This is more likely with paper or cork gaskets, but can also happen with rubber. Note that if you have to replace the oil sump gasket, get the one for 1996-up, it will fit, and it will save you a lot of wrestling.

212Kmiles is barely broken in on the RENIX castings - you're good to go for a while. I've got 280-300K on my 88 (need to fix that odometer...) and I still don't feel any qualms about getting in and driving coast-to-coast. Especially since I finally got rid of that damn Peugeot gearbox...

Since you've got a Limited, you should have the AW4 (my 89 Limited does,) and that's a good, solid slushbox. There aren't many that I would compare favourably to the AW4 - the old cast iron Powerglide comes to mind. Note that the AW4 does not like Chrysler ATF +3/+4, and probably won't like a switch to synthetic fluids. The AW4 clutches are a bit picky that way (but that transmission lives well behind the turbocharged Toyota I6 in the Supra, so just give it what it wants.) The transfer case (should be an NP242) doesn't care - just give it the same fluid you give the transmission and you'll be fine. Use Dexron II/IIE/III (any one of those) for the AW4 and NP242.

You can find a batch of tech info at my website - I cull it from Factory Service Manuals, so it's all accurate (save fluids in the AX-15, although I think I fixed that.) If you don't see anything there that you want to know, feel free to ask - since I've got nowhere near all the information I've got to hand up there yet.... Link in sig.
 
For your low idle at stoplights I would try the EGR valve. From time to time it will malfunction and cause this. You can pull the vac line off the side of it to test if that's your problem or not. If it is, disable the damn thing.
 
Double post, sorry.
 
@ 5-90
I was poking around under the hood for a while, and didn't see anything out of the ordinary (besides the block being covered in oil....usual 4.0L issue, from my exp.) No fuel smell, and everything seems to be in good shape. BTW...the link in your sig came up bad for me....PM me a good one??




I've got a 1000+ mile trip coming up here in about 3 weeks, so I'm hoping to have all the major issues worked out by then. If something was going to fail/start leaking on me, it should happen by then, right?? So far, I must say that I've been impressed. First night in the driveway, I had a small oil spot (from the rear main, I'm assuming), as well as a clear puddle in the front. I would say it was water, but it had an oily feeling to it....any ideas what that was?? I guess my XJ was just marking it's territory =P

*short rant starting.............here!*
I'm a college student currently (well, not in school, just paying for the damn loans. Still broke, tho....) and don't have a whole lot of spare $$ to throw at the Jeep. I guess the point is this: I know there are about a million things that need done to my XJ. Some things take precidence, however. Door panel rust?? Not very important. Stuck injectors/tune up needed?? Much more important. I'm very grateful for all of your help, and don't want to turn away *any* ideas. But on the other hand, I need to come up with some way to DIY everything on the cheap.....
*rant ending....................now*


Something else that's been driving me bonkers. I can't get the damn power seats to work, on either driver's or passenger side. I'm only about 9-12" taller than the lady who used to drive it....so it's getting to be *very* uncomfortable to spend any length of time on the road. Any ideas?? (Also, the fuse panel is hidden behind that trim panel under the steering wheel, right?? That would be the first place I would start, but I can't seem to find the damn thing.......)


Final question for the night. I've been told that some of the older XJs will let you pull codes from the computer by turning the key on-off-on-off-on, then just count the number of times the CEL light flashes. That's all fine and good.....but according to the owner's manual, my XJ doesn't have a CEL or SES light!! I've got idiot lights for everything else under the sun, though.....someone *please* correct me if I'm wrong!!
 
Last edited:
Your rear main is almost definitely leaking at that mileage. It probably won't get much worse over a 1,000 mile trip, but watch it. Up front could be a small drip from the radiator or the seal behind the harmonic balancer leaking (front main seal), depending on if it was truly oil or antifreeze.

The fusebox is under the steering column behind the lower trim panel.

Renix (1987-1990) 4.0 Litres don't have a check engine light. The computer system doesn't store codes unfortunately. In 91 they introduced OBD-I which is what you're referring to. And please...get a full cluster to get rid of the idiot lights, those things suck!
 
RENIX does not "store" or "throw" codes - it's pre-OBD. Most troubleshooting can be done with a DMM. There are a couple of tests that want an analogue meter (function check on a couple of sensors,) but that's not needed unless you're going to really get into it. So, no CEL, no MIL, no SES lamp, and no codes to worry about. Don't bother cycling the key, it don't do nothing (I go roundy-rounds on this with the smog techs every time I take a rig in for a smog...)

That should be a good link - but Geocities is throwing timeout errors, so it may be something on their end. I'll keep checking.

Clearish with an oily feeling? Was it up front, sort of on the driver's side? May be power steering fluid - usual suspects there would be a hose join (most common) or a leaking Pitman shaft seal (which is just enough of a pain in the arse to replace that you may find it easier to just swap the entire gear.)

For the power seats, there should be a 30A circuit breaker (silverish rectangular box) in the fuse panel to protect those motors. If it's blown for good, you can replace with a 30A ATO fuse while you find another one. If it's not. let me know and I'll give you FSM test information. I've got a 1990 FSM, but the 1989 and 1990 wiring is much the same (same control system from 1987-1990, but ChryCo changed some of the wiring colours when they took over in late 1988.)
 
I checked inside the pwr steering pump, the fluid appears to have a reddish tint. However, my puddle did not. The only thing I thought it could be was brake fluid, but it wasn't under a wheel, but sort of left-of-center, just forward of the axle. IDK...it hasn't done it since that first night.

Speaking of brakes....my brake pedal is stiff, but when I push it down, it doesn't seem like I stop. My wife's Blazer had the same issue....after a brake change and good bleed, now you just have to breathe on that pedal to stop. I'm hoping that a good bleed is all that I need on this XJ, I believe the brakes were replaced not too long ago.....
 
RaccoonJoe said:
@ 5-90
I was poking around under the hood for a while, and didn't see anything out of the ordinary (besides the block being covered in oil....usual 4.0L issue, from my exp.) No fuel smell, and everything seems to be in good shape. BTW...the link in your sig came up bad for me....PM me a good one??

Looks like Geocities is playing nice again - site's back up. Link should work now...
 
RaccoonJoe said:
I just purchased an 89 XJ Limited, with the 4.0L and the auto tranny. It's been around the block a few times (212K miles), but still seems to run strong. I've got a few questions about it, tho....

I drive an average of ~600 miles per week, so this XJ is going to mostly a road vehicle...with the 4WD coming into play on some of the county roads out here, or if I have to make a pit stop in a cornfield somewhere :shhh:

Here come the questions:

As far as I know, the XJ was driven daily by an old, handicapped man since it was new. He sold it to my buddy, whose wife drove it for 5k miles before deciding she didn't like the MPG. Then it sat around for 3-5 months, getting run just long enough to make it across the driveway once in a great while. What should I be looking for, preventive maintenance wise??

I've put about 200 miles on it so far, and just at a rough guess (without a calculator), I'm getting about 15 MPG (60% highway, 40% city) Anything I can do to improve this??

I've noticed 2 other potential problems.....I have a real bad fuel smell when starting it in the morning, like it's running *really* rich. I also have an incredibly low idle when sitting in gear at a stop light. (low as in 200-300 RPM, Jeep starts to shake and rattle, feels like it's trying to stall, etc....)

So far.....
Repairs Needed:
Oil Change
Seafoam in the vacuum lines (should I do this?? why or why not??)
Spark plugs/wires
Distributor cap/rotors
Track down and fix neg. battery cable/grounding strap issues

Repairs done:
Seafoam into new tank of fuel


OK, time for an update. I've gotten some miles down on the XJ now, and I'm averaging about 16-18 MPG, 50/50 hwy/city. Just got done with maintenance this weekend, so the to-do list now goes something like this....

Work needed
Cap/rotor (maybe)
Front seat replacement
Track down/resolve brake pedal issue
Track down left front issue

Work done
Oil change
Spark plugs
Fuel filter
Ground issue resolved
Seafoam in fuel and vac. lines

A few questions came up from this weekend's worth of work, however. I noticed that every one of the spark plugs had a nice coat of light brown crap on them, kinda like they had been gently burned (the Haynes manual put it somewhere between "normal wear" and "ash covered". Is this normal??) Put in the new plugs, and it seems to be a hair more responsive to the skinny pedal.

Changed out the fuel filter, and now my fuel pump is making a high-pitched whining/bubbling sound. It sounds like like a GM fuel pump....Especially loud inside the cab, and while cranking the motor. Is this a sign of fuel pump going out?? Do I have air bubbles in the fuel rail somewhere??

Finally, I screwed around with the wiring for the power seats. Turns out there was some sort of power + ground issue. Ran jumper lines, the seats started working again. Unfortunately, I've only got about 50% function out of them. Looking at replacing them with seats out of MX-7 or mid 80's Daytona......I'm wondering if anyone has done this before, or how big of a project am I looking at??


Thanks
Paul
 
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