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Engine/Transmission (1994 - 1998) Alternator, regulator, anything else?

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Engine/Transmission (1998.5 - 2002) Questions on a Comp

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I just replaced the timing gear case due to kdp damage. Now that I got it running again, my voltage needle bounces, lights flicker and its kinda rpm related. doesn't do it all so much at idle as much as at higherrpm, even sitting still. I checked out other threads and no one seems to have had this problem. I think when my KDP went, the oil got on the brushes, but im not sure if thats the case. I also have had a lot of fuses just strangely blow lately too, and replacements blow too... horn, A/C, dome lamp, power mirrors, engine hood lamp. thats all i noticed so far. Possible something shorted out and fried my PCM causing the charging to fluctuate? Motor runs fine... great



Thanks in advance
 
If you had the case off, you probably had to disconnect the engine speed sensor connector. This might be suspect as intermittant connections here are frequent. Does your tach work well, no small jumps or unusual glitches? If so, or even if no tach problems are apparent, check that connector carefully. The PCM needs an input from the engine speed sensor in order to activate the charging system.

Flickering lights are an indication that your charging system is intermittant and you are seeing it more at higher enging speeds because the alternator is capabile of higher output at higher speed.

There is a way to check to see it the pcm is sourcing the alternator as it should. It involves measuring the supply to the alternator which should be at battery voltage as supplied through the ASD relay, and the return line to the PCM which is sinking current and should be only a few volts when a high charge is being called for. If these two voltage readings are solid while flickering occurs, then brushes might be suspect.

Rog
 
hey thanks for your help, i'll check it out today on lunch break. When i said RPM related i meant that say maybe at idle its solid, 1000 will be jumpy, 1200 solid again and so on not really just a ok at low rpm and bad at higher. it actually seems to charge better uppon accel then decel even if the RPM's match. i didn't disconnect the RPM sensor, just moved it out of the way and positioned it at the same spot and my tach seems smooth. I'm thinking brushes seeion as how my alternator got soaked in oil
 
also when i pull the alternator fuse, voltage is steady so im sure that rules out heater grids, tach lead, light switch, and grounds. i replaced the alternator, no luck tho:( guess i'll throw in an external regulator next. btw, my cruise control still works, A/C does not tho, still possible PCM?
 
Sounds like you've got a bear lose wire + that randomly making contact to ground , I would from other post look at acessory wire in steering colum area , but if this started after doing the KDP then see if something happened in that area, but being intermitent it could take a lot of time to track down. Also insted of replacing parts find a plastic safe contact spray cleaner to clean out oil and find whats wrong so you only buy the parts you need.
 
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My truck developed the same symptoms a week ago. I am using a first gen. Nippondenso alternator. Checked wiring and replaced the external voltage regulator, still NG. Local rebuilder found a bad diode and worn brushes in the alternator. Now the fluctuation is not as bad but it still is not solved.
 
If I get the chance I will help, bring her up to my shop tomorro afternoon, I will be wrenching on my junk as soon as I put the KW back together and fix the one dump truck. :cool:



ps: BRING BEER!! :-laf
 
no cracked blockx though! Gotta look at the casting #'s good. lol. I'll see you round 12-1pm then? :-laf
 
seriously though, i think we can figure this out, I rewired a 93 after the computer went, I can definatly do a 97'... . how many togle switchez do you want???? lol :-laf
 
I thought my alternator went out today. Guage dropped to zero. I thought this odd since a bad nater usually drops the guage to the voltage held by the battery. I removed the nater and went to the rebuilder I used to work with. He tested it and it was good. He then told me that he has seem the ECM go bad and lose charge ability. Rather that buy a new ECM, he suggested I go to an external regulator on a different Chrysler nater. This required only minor wiring. I took the nater home and put it back on, cleaning all connections. It has worked ever since, so I didn't need to convert. If you need instructions on the conversion, call Greg at 386-364-1206. He owns the auto electric shop here locally. Tell him Chris told you to call.
 
Well, obviously you didn't get my humor... . :-laf However this saturday (the 22nd) I am technicaly off, if you would still like to have your rig looked at by a few mechanics bring it by my shop between 7-12. Fatboy, Seagul, and I will all be there. Prehaps one of us will come up with an Idea. I know we are all dumb diesel mechanics, however sometimes we do get lucky. ;) lemme know.

JD
 
My charge fluctuation is now solved. I used a relay to send the signal from the battery to the alternator. I used the old signal wire to trigger the relay. The voltage was steady with a temporary jumper in place so I added the relay.
 
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