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  #1  
Old February 25th, 2008, 22:27
DanMan2k06 DanMan2k06 is offline
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Car Wash WTF???

So today it was nice out and I decided to give the jeep a bath. Evyerhting went normal. Pressure wash undercarriage, outside, and select engine parts (oil pan etc...). Well I finshed it up and took it for a drive. The belt had a slight chirp when I first started driving, but it went away after a few minutes. Ok nothing abnormal. Then things started going bad. My voltmeter slowly climbed to around 16 volts, and then suddenly pegged at 19 and my check gages light came on. WTF? I pulled over and turned it off, restart, same thing. It would go to 16 for a few seconds then jump back to 19. I thought my electrical system was going to fry?!? So then I decided to keep driving to my destination, a few miles up the road. I had no phone on me, so no choice basically. Then the tranny started acting up. Torque converter locking and unlock, lots of bucking, and it shifted around 3000-3200 rpms. Anybody have any kind of clue as to what in the hell is going on? I've never seen anything like this. And I've done much more severe car washes when it was sloshed with mud, so I don't know if its the water or not. Please help me out!
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Old February 25th, 2008, 22:52
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ty20404 ty20404 is offline
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Re: Car Wash WTF???

check the connection between the alternator and battery. I had the same problem, well the pegging of the voltmeter and what not. The cable b/w the alternator and battery was extremely corroded and that's what was causing it.
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Old February 25th, 2008, 23:03
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8Mud 8Mud is offline
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Re: Car Wash WTF???

I may be way off here, I've never messed with a late model Chryco Alternator before.
But the PDC controls the field current (amount of juice the alternator puts out) through through the PCM to ground. It sounds like a shorted field winding, but theoretically it should charge higher than 19 volts if this is the case.

I'd blow out the alternator with air, pull the two small wires from the alternator (think they are green and orange) and make sure the connector is dry coat them with die electric grease.

The orange wire is ignition voltage, the dark green is the regulator wire to the PCM. If the dark green wire is shorted someplace, it could cause run away charging.

Hopefully you have a moisture short to ground and when it dries out, things will stabilize, worst case is the regulator in your PCM is toast.

Cleaning the power cables like mentioned isn't a bad idea, the charging is regulated by feedback. If the system sees low voltage at one end (the run circuit) it will try to compensate at the other end (the alternator).

Last edited by 8Mud; February 25th, 2008 at 23:07.
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Old February 26th, 2008, 17:14
DanMan2k06 DanMan2k06 is offline
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Re: Car Wash WTF???

Sounds good, I'll clean all the connections and give them a lube. However, my transmission is still shifting waaaay to high. Like 2500 at the lowest, and the shifts are extremely rough. Today it only did it once, and after re-starting the car and putting it back in drive it went away.
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Old February 26th, 2008, 22:05
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UNCC_99XJ UNCC_99XJ is offline
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Re: Car Wash WTF???

Quote:
Originally Posted by DanMan2k06
Sounds good, I'll clean all the connections and give them a lube. However, my transmission is still shifting waaaay to high. Like 2500 at the lowest, and the shifts are extremely rough. Today it only did it once, and after re-starting the car and putting it back in drive it went away.
This is a long shot, but......the system might have gone into "shock" and be "recovering"...for lack of better terms. For example, when my step brother was helping me install my amp one day, he accidentally made a connection between the battery and the top of the AC compressor with the ratchet he had in his hand...causing a nice little spark (Didn't listen to me when I said unhook the battery....), and in turn, shorting out my electrical system. I got back in the Jeep to find all my gages pegged, and when I had my door open and the key in the ignition, every time the chime sounded from the key in the ignition, the gages moved back down to zero. After that, I had to be somewhere ASAP, and the Jeep wouldn't run. It would sit there and crank all day, unless I gave it some gas. I already had a failing TPS that was causing that no run symptom, and I think this "shock" was what did it in. I ended up replacing the TPS the next day.

Drive it again for a couple more days and see if it's still doing it.
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Old February 26th, 2008, 22:39
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8Mud 8Mud is offline
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Re: Car Wash WTF???

Most anytime my PCM starts acting up I disconnect the battery for awhile and reboot.
Could also be some moisture in your TPS, causing the shift problems.
Hopefully the voltage spike didn't do any permanent damage.
You could have a couple of unrelated moisture induced problems or the voltage spike caused some programing glitches.
There is a TSB out warning about voltage pulses to the voltage regulator in the PCM. They recommend making sure the key is off before removing the PCM connectors, I always go one step farther and disconnect the battery.
If your troubles are a sometimes thing, it's unlikely they are permanent. Wet connectors and line leaks seem a likely cause.
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