98 TransAm Alternator issues, help?
98 TransAm Alternator issues, help? I've done a search and the answers are confusing. I have a 98 TA with what I believe is an alternator issue. Symtems: Fluctuating charge meter, lights pulsating and the dash meter never reads above 13 volts, also the main belt tensioner was also constantly moving back and forth about a 1/2 inch.
I took it to Auto Zone and they tested the alternator and battery in the car. It showed the battery was bad but the alternator was ok. I bought a new battery and installed it. For about 15 seconds the belt tensioner held steady but then started moving again. ( I replaced the tensioner a couple days ago without any change). I cleaned the grounds coming off the battery but no change.
I pulled the alternator, Delco Remy (replacement?) and noticed the exciter wire had been spliced. Took connector apart and noticed a slight wiggle in the metal connector on the end. Made another wire and spliced it in with a butt connector up by where the wiring ties into the main bundle.
I put everything back together, no pulsating lights, tensioner is steady but now it appears my battery is not charging, needle in the caution area 11 volts or less. My searching has shown you can use a truck alternator (2005 Chevy 2500 w/6.0?) It appears the same except does not have the boss for the smaller rear bolt. Will it work?
Also, my searching has shown that the wiring for the 98 is different than the 09-02. Does the red wire (exciter) go to the PCM or somewhere else?
I've read about placing a resistor in line and running it to 12 volts keyed and as also read that this wire should only see 4-5 volts, confusing. Can anyone help.
Thanks
John
I took it to Auto Zone and they tested the alternator and battery in the car. It showed the battery was bad but the alternator was ok. I bought a new battery and installed it. For about 15 seconds the belt tensioner held steady but then started moving again. ( I replaced the tensioner a couple days ago without any change). I cleaned the grounds coming off the battery but no change.
I pulled the alternator, Delco Remy (replacement?) and noticed the exciter wire had been spliced. Took connector apart and noticed a slight wiggle in the metal connector on the end. Made another wire and spliced it in with a butt connector up by where the wiring ties into the main bundle.
I put everything back together, no pulsating lights, tensioner is steady but now it appears my battery is not charging, needle in the caution area 11 volts or less. My searching has shown you can use a truck alternator (2005 Chevy 2500 w/6.0?) It appears the same except does not have the boss for the smaller rear bolt. Will it work?
Also, my searching has shown that the wiring for the 98 is different than the 09-02. Does the red wire (exciter) go to the PCM or somewhere else?
I've read about placing a resistor in line and running it to 12 volts keyed and as also read that this wire should only see 4-5 volts, confusing. Can anyone help.
Thanks
John
Last edited by jhmws6; Aug 6, 2009 at 10:19 AM. Reason: grama
Hey John i am in the same boat as you 
I've tested my battery and it seems to be fine. I think the diodes in the alt are going bad..
Read my thread, tell me what you think. I got some help but not much.
We are experiencing the same symptoms
https://ls1tech.com/forums/stereo-el...me-inside.html
I've tested my battery and it seems to be fine. I think the diodes in the alt are going bad..Read my thread, tell me what you think. I got some help but not much.
We are experiencing the same symptoms
https://ls1tech.com/forums/stereo-el...me-inside.html
Torchd,
You stated in your post that you had some corrosion on your positive terminal and that when you cleaned it seemed to correct it for a little while, right? Have you checked to see if maybe your cable is corroded on the inside? Just a thought, I'll let you know what I come up with, I need to fix this problem.
You stated in your post that you had some corrosion on your positive terminal and that when you cleaned it seemed to correct it for a little while, right? Have you checked to see if maybe your cable is corroded on the inside? Just a thought, I'll let you know what I come up with, I need to fix this problem.
Torchd,
You stated in your post that you had some corrosion on your positive terminal and that when you cleaned it seemed to correct it for a little while, right? Have you checked to see if maybe your cable is corroded on the inside? Just a thought, I'll let you know what I come up with, I need to fix this problem.
You stated in your post that you had some corrosion on your positive terminal and that when you cleaned it seemed to correct it for a little while, right? Have you checked to see if maybe your cable is corroded on the inside? Just a thought, I'll let you know what I come up with, I need to fix this problem.
Did you replace your positive cable?
Well I'm pulling the alternator tonight and having it rebuilt tomorrow into a true one wire. That will eliminate any issues with the exciter wire. I'll let you know if this cures my problems.
John
John
BTW did you replace your positve wire... From the battery to the right side of the car that goes onto the fuse block?
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a couple more things ruled out Well my positive cable is fine, checked voltage at battery and again at alternater, they are the same. Also checked to make sure voltage is at the exciter (sp) which has between 6-7 volts. Alternator is out and will be rebuilt tomorrow.
John
John
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Verdad Gallardo What was your battery reading?? 13.8-13.9... How do you check voltage at the alt?
Battery was only reading 12.4 volts and by switching the red lead from the positive side of the battery to the post at the bottom of the alternator (where line from battery connects) it also read 12.4, so all the voltage from the battery is being supplied to the alternator. I figure if the cable was corroded I would see a difference it voltage between the 2. Check the thread by Pro Mouse tonight ref. check gauge light.... I explained how I checked the exciter wire.
Battery was only reading 12.4 volts and by switching the red lead from the positive side of the battery to the post at the bottom of the alternator (where line from battery connects) it also read 12.4, so all the voltage from the battery is being supplied to the alternator. I figure if the cable was corroded I would see a difference it voltage between the 2. Check the thread by Pro Mouse tonight ref. check gauge light.... I explained how I checked the exciter wire.
new update Dropped the alternator off this morning should have it back this afternoon and car up and running tonight. Had them check the alternator and at first it was working fine, putting out about 105 amps. After about a minute output shutdown. The tech thinks whats happening is that the brushes are worn and barely making contact and when the case heats up it expands and the brushes loose contact. keeping my fingers crossed.
John
John
Dropped the alternator off this morning should have it back this afternoon and car up and running tonight. Had them check the alternator and at first it was working fine, putting out about 105 amps. After about a minute output shutdown. The tech thinks whats happening is that the brushes are worn and barely making contact and when the case heats up it expands and the brushes loose contact. keeping my fingers crossed.
John
John
I am intrested to see what happens when you get yours back now.. Keep me posted!!!!
Success 
Well I picked up my rebuilt, true 1 wire alternator and installed it. Charging 14.4 volts and no issues. My pulsating lights and tensioner have gone away. Just taped up the exciter wire tucked it away. The shop put a cap over the 4 pin connector on the alternator. Cost was 98.99John
Well I picked up my rebuilt, true 1 wire alternator and installed it. Charging 14.4 volts and no issues. My pulsating lights and tensioner have gone away. Just taped up the exciter wire tucked it away. The shop put a cap over the 4 pin connector on the alternator. Cost was 98.99John
What were you experiencing with the tensioner again?
Drive it more to see if the 'problems' coem back...
The alternator has only one wire, the cable from the battery. It no longer uses the exciter wire that would normally plug into the top of the alternator. My tensioner was also moving back and forth, I'm not sure but due to my issues with the alternator I think maybe the motor was surging a little bit? Anybody else have any ideas about the issue with the tensioner? I let you know if any issues pop up.
John
John
Lucky you.. And man that is soooooooooooo annoying looking at it, espically coming to a stop light. The volts drop, ALL lights dim.. Man i can not wait to get mine fixed then