1993 Trans Am LT-1: Charging problem
06-24-2007, 03:43 PM
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1993 Trans Am LT-1: Charging problem Hi guys, the F-Body thing is all new to me(was a 5.0 guy) but so far i am enjoying it.
Small issue on my 1993 T/A. It seems that the charging indicator always reads into the yellow/low area, somwhere around 10. Doesnt seem to matter whether or not the stereo is on, lights on or off, the indicator is always in the yellow. It never goes below that mark, but it never gets above it either(i think around 13 should be normal..?). The battery is brand new. Is this something to be concerned about? Any ideas are appreciated. Thank you.
Phil
Small issue on my 1993 T/A. It seems that the charging indicator always reads into the yellow/low area, somwhere around 10. Doesnt seem to matter whether or not the stereo is on, lights on or off, the indicator is always in the yellow. It never goes below that mark, but it never gets above it either(i think around 13 should be normal..?). The battery is brand new. Is this something to be concerned about? Any ideas are appreciated. Thank you.
Phil
06-24-2007, 03:50 PM
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The sensors in the Fbodies are notoriously inaccurate. My battery gauge reads high, our tachs read ~100-200 rpms high, the low coolant sensor likes to come on even if the radiator is full, and my oil pressure gauge has went before too(although that doesnt seem too common).
My advise is to test the battery when the car is off with a digital multimeter, then turn the vehicle on and check it again. It should read higher if the alternator is charging it correctly. If you get the same reading, then you will have to look into alternator and/or wiring problems.
Welcome to the crowd though! There are a ton of LT1 boards floating around, and although the aftermarket is not as big as the 5.0 scene you shouldnt have any problems reaching your goals and getting any help you need.
My advise is to test the battery when the car is off with a digital multimeter, then turn the vehicle on and check it again. It should read higher if the alternator is charging it correctly. If you get the same reading, then you will have to look into alternator and/or wiring problems.
Welcome to the crowd though! There are a ton of LT1 boards floating around, and although the aftermarket is not as big as the 5.0 scene you shouldnt have any problems reaching your goals and getting any help you need.
06-24-2007, 03:58 PM
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Originally Posted by Puck
The sensors in the Fbodies are notoriously inaccurate. My battery gauge reads high, our tachs read ~100-200 rpms high, the low coolant sensor likes to come on even if the radiator is full, and my oil pressure gauge has went before too(although that doesnt seem too common).
My advise is to test the battery when the car is off with a digital multimeter, then turn the vehicle on and check it again. It should read higher if the alternator is charging it correctly. If you get the same reading, then you will have to look into alternator and/or wiring problems.
Welcome to the crowd though! There are a ton of LT1 boards floating around, and although the aftermarket is not as big as the 5.0 scene you shouldnt have any problems reaching your goals and getting any help you need.
My advise is to test the battery when the car is off with a digital multimeter, then turn the vehicle on and check it again. It should read higher if the alternator is charging it correctly. If you get the same reading, then you will have to look into alternator and/or wiring problems.
Welcome to the crowd though! There are a ton of LT1 boards floating around, and although the aftermarket is not as big as the 5.0 scene you shouldnt have any problems reaching your goals and getting any help you need.
06-24-2007, 05:46 PM
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My tach reads dead on >_> Well, with my ECM at least it's on. Then again, I was only looking while sitting at a light. I suppose I could hold the scanner up twords the windshield and look between while cruising with the RPMs up there a bit more. I don't know about 94+ cars, I'd assume it wouldn't matter though.
I do agree with the multimeter test, best way to tell. Shouldn't it be more like 13.5-14.5v running?
I do agree with the multimeter test, best way to tell. Shouldn't it be more like 13.5-14.5v running?
06-24-2007, 10:12 PM
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You should check out www.speeddensity.org is you want some specific info on 93's.
But it sounds like your alternator is going out. You should have around 14 volts on the back of the alternator while running.
But it sounds like your alternator is going out. You should have around 14 volts on the back of the alternator while running.
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06-25-2007, 12:51 AM
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the low coolant sensor likes to come on even if the radiator is full
06-25-2007, 02:20 AM
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Hmm, well i dont have a MM on hand, so i will grab one tomorrow.
Something else i noticed....when i first start the car, there is weird 'feedback' from the right side speakers when the stereo is on....the amp gauge reads low when it happens. After i drive for maybe a minute at most, there is almost like a split second drop(or surge?) in electrical power, which is noticable because the lights will dim for that second and return to normal. Then, the feedback sound goes away and the amp gauge reads close to normal, about 12. Do i have severe electrical gremlins in my car!?
This is kind of freaking me out...
Something else i noticed....when i first start the car, there is weird 'feedback' from the right side speakers when the stereo is on....the amp gauge reads low when it happens. After i drive for maybe a minute at most, there is almost like a split second drop(or surge?) in electrical power, which is noticable because the lights will dim for that second and return to normal. Then, the feedback sound goes away and the amp gauge reads close to normal, about 12. Do i have severe electrical gremlins in my car!?
This is kind of freaking me out...
06-25-2007, 03:01 AM
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bad ground wire somewhere
as for the charging question. my alternator had a bad regulator. it would allow it to get over 10volts. made starting the beast a pain in the but. plus it would die while driving, and then all of a sudden it quit and ran off the battery until it was dead. I tested it and found out that it was bad, replaced it with a 140amp one, I had to change my connector from a square to a round...but now it runs great and I actually get around 13.
as for the charging question. my alternator had a bad regulator. it would allow it to get over 10volts. made starting the beast a pain in the but. plus it would die while driving, and then all of a sudden it quit and ran off the battery until it was dead. I tested it and found out that it was bad, replaced it with a 140amp one, I had to change my connector from a square to a round...but now it runs great and I actually get around 13.
06-25-2007, 03:02 AM
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actually the more I think of it...the lights dimming....might be the regulator as well. mine did that until I replaced the alternator....hmmmmm. I'd have it tested
06-28-2007, 11:29 PM
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Originally Posted by FAD2BLK93
+1 on the grounding issue...but are the lights dimming because the fans have turned on...and if the fans are running at start up then you may have some DTC's.
Gah...grounding issue. Could it also be a voltage regulator? Alternator? My MM died before i could even test my charging situation....but i am concerned about this electrical issue. Seems to be constant, and the quick surge/drop in power i get happens usually right after i start to drive away. At this point, the Amp gauge jolts down, then back up, and i can hear the surge through the speakers in the stereo, if its on that is.
I think my left turn signal relay/switch is out. The right turn signal works just fine, but the left one doesnt do anything at all. When the lights are on at night, the left turn signal indicator on the dash is always 'lit' up like its on, but nothing. Ack!
