OPNJ

My 1998 xj classic 4.0L straight 6 has a bunch of problems. I bought it from a friend about a year and a half ago (May 2011). I'm just gonna put down as much info as I can so that everything is in the open and maybe people can help me fix at least some of these problems and because maybe there's a connection between some of the problems that I'm not seeing.


- The gages and passenger power window controls work intermittently (the driver window controls work) and the driver side power door lock switch doesn't work, but the unlock switch work (both lock and unlock switches work on the passenger door)----was like that when I bought the car and still is like this

- It also had a some trouble starting up when cold, (it would crank for awhile before finally turning over) but would start right up if it had been driven shortly before. It got worse and worse until August when we finally checked it out and found out the fuel pump was bad so I replaced it.

- In September, I had to replace my breaks and master cylinder

- Then about a week later, I was having more problems with the ignition and found out in February the neutral safety switch was going bad so I replaced that too (I would turn the key but it wouldn't even attempt to crank- and every other possible culprit checked out).

- It ran fine for about a month, before the same sluggish start up began happening again. It also occasionally would make these awful rattling and clanking noises at start up and then just die. I waited 2 or 3 seconds and tried again and it started right up. I just left it because I didn't have time or money to do anything about it and it still ran so I could live with it.

- Then in June, my battery would completely drain in a day or 2 so I took it to advanced autoparts to get the whole system checked out for free. Everything was fine (the battery and alternator - which had a slight "ripple" - were still good but were getting close to the point of needing to be replaced). After further tests, it turned out the interior lighting was shorted out and possibly the door lock actuator (or something in that circuit). I didn't feel like ripping through it, so, to stop it from draining, I just pull the fuse in the PDC (which also controls the stereo) when I'm done driving for the day and put it in in the morning---yes it is kind of annoying.

- In early July, I put some of that fuel injector cleaner additive stuff into my gas tank and put on a cold air intake and a throttle body spacer. The weird noises went away and it starts up a tiny bit faster and smoother but not that much.

- Later that month, during the brief periods that my instrument panel works, I noticed the CEL on and pulled p0138 and p0141 codes---high voltage code and the heater circuit code for the downstream O2 sensor. I waited until the end of August when I had the time to do any work on it (right before going back to school). When I finally got to it, I realized that the welds that were holding up my exhaust broke so it was resting on my frame (pulling the wires for the O2 sensor) and held up by one bracket neat the exhaust tip. So I replaced the downstream sensor (with a bosch from advanced autoparts) and the muffler/tailpipe because there were rust holes in them (and doing that also lifted up the whole exhaust system off the frame)

I drove about 600 miles before checking the codes again (to complete a drive cycle and give the computer time to reset itself), but the codes were still there. I reset the computer and did even more driving. During that time, when my instrument panel was working, the CEL was on so the codes were obviously still there; but then the gages would drop out, and the "check gages" light immediately came on.

I ignored it until today when I got bored and decided to check the codes to see if they were still there....They were, as well as p1682 (charging system voltage too low) and p1698 (no bus message from transmission control module)


I was wondering:
Regarding the charging voltage and O2 sensor codes: could the the O2 sensor codes be remaining on because the alternator or battery might be going bad (but didn't trigger the p1682 code until recently). Or, could the "charging system voltage too low" code trigger because of a short in the heater circuit or a faulty sensor; even if the battery and alternator are still ok?

Regarding the p1698 code: does this have something to do with the instrument cluster or something entirely different? The transmission seems ok when I'm driving (it seems to shift fine and I haven't noticed any real difference in the throttle response except for a small increase when I put on the new intake and tbs)

If anybody has had any of these problems and knows where to start or how to fix any of them, I would greatly appreciate the help. This has been one problem after another and I just don't have the time or money to have a mechanic try to diagnose and fix everything


I'm going to try to work on resolving the bigger issues tomorrow and start off by cleaning all the terminals/connections on the instrument panel and solidly reconnecting everything to hopefully fix the gage issue; then take it down to get the battery and alternator checked out before I start doing continuity tests because I feel like those issues could be related (but I could be completely wrong). If the battery and alternator both check out good then I guess I should check for continuity in the heater circuit before I assume a faulty replacement O2 sensor and spend money on another one that may not be the problem. But I don't really know how to attack the p1698 code until I really understand what it means.



- John

OPNJ

The test report from advanced auto parts came back good. The battery is putting out 12.58V, 882cca (rated at 630), and a temp of 112F. The starter has a voltage of 11.13V, 0.0A and time=1.57s. The alternator is putting out 13.71V under no load, and 13.62V loaded, and has a ripple of 44mV. I didn't clean the instrument panel terminals or check for continuity in the heater circuit yet, but was really hoping that somebody could point me in the right direction as to what else could be causing these problems and how to fix any of them if they had the same problems too.

CCKen

Looks like you've been baptized into a world of XJ chit brother.

In '98 (I think) Chrysler issued a TPS to address inop instruments. Basically, it called for replacing the instrument cluster connector. A splice-in of a new connector, which is available at the dealer.

Looks like you are now familar with batteries and alternators. One thing I suggest is that you look over every square inch of the wiring harnesses in your engine bay for chaffing and exposed wiring.

Next, address every ground point in the engine bay. Check for corrosion by disassembling the ground attachments and examning the terminal ends for defects, and clean them if required. Below are photos of all the engine bay ground points in case you weren't familiar with them. Some may have nothing to do with your problems but be a good Boy Scout and check them any way.

Rockville

Ground pictures should be "sticky". Nice info, CCken!!!

OPNJ

Thanks for the response CCKen. I'll try to get out tomorrow to do all that, as well as clean/wipe down everything else in there while I'm at it because it's all pretty grimy and is also just good practice. And I read about that splice-in connector before I made this post, but figured I should try cleaning it and try making a solid connection before I start buying things because, unfortunately (and very inconveniently), I'm a broke college kid that is on an insanely strict budget until summer when I start working again (or my parents begin to feel bad for me and give me some money; which is very doubtful). It also may take awhile to do these things because I don't have that much free time up here anymore (because my grades suck and I seriously need to bring them up so I don't get kicked out) and also don't really have any tools here to get the work I need to do done. But I will update this with the results as I do things or if/when I run into any problems

g36pilot

x2 Sticky

Thanks for posting CCKen

jeepsurfer1

I've been there, went wire by wire, starting with sensors and ending at the plugs, it was a two week procedure, never again