XJ has different "modes"???

Well my Jeep has started acting VERY weird. It's like it has 3 different modes that it wants to be in - while never being in 2 at the same time. So here they are:

(1) Normal. This seems to only happen when I am parked, start the car, and go immediately into drive (quickly). Shifts are consistent and right on the mark. Torque converter disengages when I let off the gas, and downshifts are normal under load.

(2) Mode 2. Weird. This happens if I take a sharp turn slowly. The steering wheel get VERY hard to turn and the car stutters for a second, sometimes twice. After the stutter the shifts are higher than normal (by maybe 150-200 rpms) and are not smooth at all. The torque converter also will not unlock after reaching overdrive. I have to tap the brake to disengage it or use the stick to downshift. If I do manually downshift with the stick into 3rd, it acts the same way, and will not unlock unless the brake is tapped.

(3) Ridiculous mode. This one sucks. It happens everytime I go into reverse. While in reverse the car bucks and stutters, until it is put into drive. If put into neutral or park after reverse, it idles around 1200 rpm's. It hates shifting, and does so way, way, way too high. from first to second, if it is under a normal load, will shift around 3200-3400 rpm's. The rest aren't much different, maybe a little lower. Again the torque converter doesn't like to disengage. I cant stand driving in this mode, so I turn the car off (only work in park, not neutral) and restart. Everything is reset again by restarting.

I'm completely stumped. It's been happening ever since I had that freak carwash that spiked my voltmeter up to like 19. Ever since then the tranny has been acting very weird. I'm going to change the fluid tomorrow, but it definately seems like an electrical bug. Anyone have any ideas? '97, AW4, NP231.

TPS...

I dont want to sound rude. but thats kinda funny. ridiculous mode. ha.

throttle position sensor, its on the side of your throttle body.

X3 TPS Check the readings

By reading you mean resistance and such? And yes, ridiculous mode is quite ridiculous.

Well it's not the TPS. I heated up mine and it made no difference. So I went and got another one, same thing, no difference. I'm leaning more towards the IAC now.

Very strange combo indeed. I would climb under the jeep and look for a bad tranny mount, check the Tranny and NSS wiring and the vehicle speed sensor down while underneath, also check the engine mounts, check the serpentine belt for any problems for sure due to the turn power steering issue, look under the hood for any obvious wiring problem, have some one turn the steering wheel while you watch movement under the hood, check the battery and connections, alternator and PC fuse box for water or corrosion.

Also you might try disconnecting the battery for a while and reset the TCU and ECU/PCM and see if has a memory problem from the car wash shorting something out.

I would definately look for a loose ground wire problem that moves when turning corners which can also be related to a bad engine or tranny mount, pulling on the ground connection. The bad ground could be anywhere.

Check and clean and then realign the neutral safety switch.

IAC isn't read during normal operation, only when idling.

Well now it is idling very poorly. Everything seems to be amplified x100 in the rain. It will drop to literally about 150 rpms, I dunno how the engine even stays running. Then bounce up to 1200 for a minute and drop back to the low end. Also while under normal driving conditions the transmission hesitates more. By this I mean unlocking and re-locking the torque converter, downshifting to first while I'm going like 30 in 3rd.

Very strange combo indeed. I would climb under the jeep and look for a bad tranny mount, check the Tranny and NSS wiring and the vehicle speed sensor down while underneath,
I'll have to climb under and check these out. The tranny mounts are fine, but I haven't checked any sensors underneath

also check the engine mounts,
Good here.

check the serpentine belt for any problems for sure due to the turn power steering issue,
Could definitely use a new belt. Dealership quoted around $70 for one but I might just bite the bullet for an OEM one.

look under the hood for any obvious wiring problem, have some one turn the steering wheel while you watch movement under the hood,
I'll try this, even though my power steering is completely shot lol.

check the battery and connections, alternator and PC fuse box for water or corrosion.
Fuse box looks good, battery sucks but nevertheless has no corrosion.

Also you might try disconnecting the battery for a while and reset the TCU and ECU/PCM and see if has a memory problem from the car wash shorting something out.
I thought this would help as well, but when installing the new tps I disconnected the battery for a few minuted and nothing changed.

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I believe it's a combinations of things. My belt slips when it rains. My power steering blows. If the pump was seizing/going bad, couldn't the increased load on the engine cause it to stutter when going around corners at low speeds? Also, with the shifting problem. It has to be electrical due to the fact that I can turn off the car and "reset" everything. So clogged cat, or any restriction problems are out.

Check / Clean ALL Ground cables / Straps

Well I don't think it's the pump... I took it off today and the fluid was perfectly clean. It looked brand new. The pulley also spun free as a bird with only my hand. I have another pump and gearbox, but they are form a 95 so the pump is different. Any differences in the gearboxes? The idling problem is still there, and seems to be getting worse and worse.

I had strange problems from the Upstream O2 on my 98 that caused all sorts of funny things. Try unplugging that, checking the wiring etc.

I also had a chafed wire between the fuel rail and the firewall that only rubbed when I went into reverse. It would run fine all the way home, but park it and then put it in reverse, stumbling and my temp went all the way above 260 instantly.

Any CELs? Also try mashing the gas when things are happening, most if not all OBD sensors are ignored at WOT, so if the problem goes away, that could mean it's a sensor.

Hmmm I'll have to check that, the bulk of the problems happen - or seem to be triggered when in reverse. No CEL's either.

Mine is having a similar problem, except that it only has normal mode and ridiculous mode. In ridiculous mode, the blower doesn't work and turning it on makes the problems worse. I have been told it may be a vaccuum leak.

Not trying to hijack your thread, just passing on what someone suggested to me for what it's worth.

with the way its shifting wierd what about the magnetic trans speed sensors?

Well replaced the MAP sensor today and took out the IAC as well. It was jet black and covered in carbon. After cleaning off the debris I reinstalled it, and my idle was at a screaming 3000 rpm's. It slowly creeped back down but never went below 1800-2000. I'm thinking this is the culprit.

Very strange happenings there. Keep us informed. I would have bet the TPS was the culprit or a bad ground. I had to run a seperate ground to one that I had on another XJ. Without the extra ground it acted strang when shifting too, but was torque converter lock up and unlocking only. Good Luck

Maverickj1 said:

Mine is having a similar problem, except that it only has normal mode and ridiculous mode. In ridiculous mode, the blower doesn't work and turning it on makes the problems worse. I have been told it may be a vacuum leak.

Not trying to hijack your thread, just passing on what someone suggested to me for what it's worth.

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My AC blower was dying every time I gave the engine gas. Turned out to be a bad (New off the shelf, but defective ID, it was not round) vacuum hose I had installed a week earlier. Tiny vac leak, liked to never found it. Had to turn the engine off and run to hear the leak before it ran out of vacuum. The other problem was I kept looking for an electrical problem with the blower wiring. Turned out the vac leak was on the A/C damper door and A/C selector switch vac line, very think line, and any leak on it, plus the drop in engine vacuum at heavy throttle was just enough the move the damper doors from vent to defrost/windshield and it made it appear the blower was dying, when it was not.