Voltage problem only at start
robversion2004
11-12-2004, 11:28 AM
I have a '98 Buick Lesabre.
About 1 week ago I noticed that when I started the car the voltage meter showed only about 9 volts right after starting the car and then it would slowly climb to about 10 and then accelerate up to about 14. Once the car is running the voltage is fine.
Sometimes at idle the voltage will oscillate a little.
Then a few days ago I had a problem where the car cranked and started to run but then suddenly the voltage cut out and the car shut off. Also their was no electrical power at all. After a few moments the power would return or go in and out again repeatedly.
I tested the battery and it is good. While checking the alternator I noticed that the tensioner pulley bearings were bad so I replaced the tensioner. I thought that would solve the problem since it seemed that maybe the belt was being restricted in travel.
The problem persists. I can get the car to start by reving the engine high right after turning the ignition. The car will sputter at low rpm while the voltage gauge shows low voltage but then once the voltage goes above about 11 volts it will be fine and level out.
Again this problem only occurs when starting the car. Once its running everything is fine.
Any suggestions,
Rob
About 1 week ago I noticed that when I started the car the voltage meter showed only about 9 volts right after starting the car and then it would slowly climb to about 10 and then accelerate up to about 14. Once the car is running the voltage is fine.
Sometimes at idle the voltage will oscillate a little.
Then a few days ago I had a problem where the car cranked and started to run but then suddenly the voltage cut out and the car shut off. Also their was no electrical power at all. After a few moments the power would return or go in and out again repeatedly.
I tested the battery and it is good. While checking the alternator I noticed that the tensioner pulley bearings were bad so I replaced the tensioner. I thought that would solve the problem since it seemed that maybe the belt was being restricted in travel.
The problem persists. I can get the car to start by reving the engine high right after turning the ignition. The car will sputter at low rpm while the voltage gauge shows low voltage but then once the voltage goes above about 11 volts it will be fine and level out.
Again this problem only occurs when starting the car. Once its running everything is fine.
Any suggestions,
Rob
robversion2004
11-12-2004, 11:30 AM
Also I should note that I tested the alternator by running the car with the + battery cable detached and the car ran okay.
Could I be getting a short on my starter relay? I'm guessing that maybe when I engage the ignition the short will drain current to ground.
Could I be getting a short on my starter relay? I'm guessing that maybe when I engage the ignition the short will drain current to ground.
avatar307
11-13-2004, 01:47 AM
Most likely the alternators' voltage regulator is going out.
Your best bet would be to take the car to AutoZone, Wal-mart, Goodyear, Midas, etc and have them test the alternator and battery.
Testing the alternator in your driveway requires a volimeter, fused link from the battery into the alternator stator (I believe that's where it connects), and a switchable carbon pile connected to your car battery.
At least from the far too detailed instructions I've read pertaining to the function of a automotive AC alternator in a DC system.
Your best bet would be to take the car to AutoZone, Wal-mart, Goodyear, Midas, etc and have them test the alternator and battery.
Testing the alternator in your driveway requires a volimeter, fused link from the battery into the alternator stator (I believe that's where it connects), and a switchable carbon pile connected to your car battery.
At least from the far too detailed instructions I've read pertaining to the function of a automotive AC alternator in a DC system.
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