Alternator problem please HELP!
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Alternator problem please HELP! Hi guys this my situation. A few days ago I took off a traffic light pretty fast in my 98 TA. When the car hit 2 gear( it's automatic) the "check gauges" light came on. I checked my voltmeter was on the lowest yellow zone. I have a digital voltmeter and it showed 11.9 volts.
I knew it was the alternator I have replaced like 1 yr ago from pepboys. Last time I just replaced it because I got the car. I bought an Optima red top battery also. So I removed my alternator took it to pepboys, they bench tested and it was bad. The gave me a new replacement (remanufactured, I know they are crap) and I installed fired it up and everything looked good. I rev it up a few times in my driveway and no problem at all. I drove the car nicely for about 2 days and today I accelerate pretty hard so I can pass a car and the "check gauges" light came on again. Same problem the volts are way low. A good friend of mine told me that it could very well be a bad ground to the alternator. It overheats it and it goes bad( okay...). So I replace the alternator again and I put a #4 gauge wire from the chassis to one of the bolts of the alternator.
I test drive it and everything seems fine until again I rev it up while driving and the problems repeats again. I haven't checked the battery. The car starts with no problem even with the bad alternator. Could it be a bad battery? I don't know what else to try it doesn't make sense. I put the scanner and I don't have any codes.
Any ideas? Thanks. Jay
I knew it was the alternator I have replaced like 1 yr ago from pepboys. Last time I just replaced it because I got the car. I bought an Optima red top battery also. So I removed my alternator took it to pepboys, they bench tested and it was bad. The gave me a new replacement (remanufactured, I know they are crap) and I installed fired it up and everything looked good. I rev it up a few times in my driveway and no problem at all. I drove the car nicely for about 2 days and today I accelerate pretty hard so I can pass a car and the "check gauges" light came on again. Same problem the volts are way low. A good friend of mine told me that it could very well be a bad ground to the alternator. It overheats it and it goes bad( okay...). So I replace the alternator again and I put a #4 gauge wire from the chassis to one of the bolts of the alternator.
I test drive it and everything seems fine until again I rev it up while driving and the problems repeats again. I haven't checked the battery. The car starts with no problem even with the bad alternator. Could it be a bad battery? I don't know what else to try it doesn't make sense. I put the scanner and I don't have any codes.
Any ideas? Thanks. Jay
I have seen bad batteries take out alternators...what is the voltage drop from the negative post at the battery to the engine block? Also, what is the voltage drop from the positive post of battery to the main cable at the alternator?
Hi guys this my situation. A few days ago I took off a traffic light pretty fast in my 98 TA. When the car hit 2 gear( it's automatic) the "check gauges" light came on. I checked my voltmeter was on the lowest yellow zone. I have a digital voltmeter and it showed 11.9 volts.
I knew it was the alternator I have replaced like 1 yr ago from pepboys. Last time I just replaced it because I got the car. I bought an Optima red top battery also. So I removed my alternator took it to pepboys, they bench tested and it was bad. The gave me a new replacement (remanufactured, I know they are crap) and I installed fired it up and everything looked good. I rev it up a few times in my driveway and no problem at all. I drove the car nicely for about 2 days and today I accelerate pretty hard so I can pass a car and the "check gauges" light came on again. Same problem the volts are way low. A good friend of mine told me that it could very well be a bad ground to the alternator. It overheats it and it goes bad( okay...). So I replace the alternator again and I put a #4 gauge wire from the chassis to one of the bolts of the alternator.
I test drive it and everything seems fine until again I rev it up while driving and the problems repeats again. I haven't checked the battery. The car starts with no problem even with the bad alternator. Could it be a bad battery? I don't know what else to try it doesn't make sense. I put the scanner and I don't have any codes.
Any ideas? Thanks. Jay
I knew it was the alternator I have replaced like 1 yr ago from pepboys. Last time I just replaced it because I got the car. I bought an Optima red top battery also. So I removed my alternator took it to pepboys, they bench tested and it was bad. The gave me a new replacement (remanufactured, I know they are crap) and I installed fired it up and everything looked good. I rev it up a few times in my driveway and no problem at all. I drove the car nicely for about 2 days and today I accelerate pretty hard so I can pass a car and the "check gauges" light came on again. Same problem the volts are way low. A good friend of mine told me that it could very well be a bad ground to the alternator. It overheats it and it goes bad( okay...). So I replace the alternator again and I put a #4 gauge wire from the chassis to one of the bolts of the alternator.
I test drive it and everything seems fine until again I rev it up while driving and the problems repeats again. I haven't checked the battery. The car starts with no problem even with the bad alternator. Could it be a bad battery? I don't know what else to try it doesn't make sense. I put the scanner and I don't have any codes.
Any ideas? Thanks. Jay
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That was one of the things that I check the wires. I looked all the way underneath and haven't seen any problem were the wire is pinched.
Also to check the voltage that you suggested... I need to do it with a new alternator? Or can I just charge the battery? Do I need to disconnect the cables at the battery? I haven't replaced the alternator yet (again).
Also to check the voltage that you suggested... I need to do it with a new alternator? Or can I just charge the battery? Do I need to disconnect the cables at the battery? I haven't replaced the alternator yet (again).
That was one of the things that I check the wires. I looked all the way underneath and haven't seen any problem were the wire is pinched.
Also to check the voltage that you suggested... I need to do it with a new alternator? Or can I just charge the battery? I haven't replaced the alternator yet (again).
Also to check the voltage that you suggested... I need to do it with a new alternator? Or can I just charge the battery? I haven't replaced the alternator yet (again).
Just trying to help.
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No I didn't remove them but I'm going to go to friend's house tomorrow to work on it. You mean to remove all the the wires that go from the battery to the alternator, to the fuse boxes to the chassis, to the starter? The # 6 wire red and black? right? Thanks for the replies.
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You dont need to take them completely off....just take a good look at them, make sure the bolt is tight on the block. The battery has to be above 12.5 volts to properly test. Usually the tester will tell you if you need to charge and retest.
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Thread Starter
Teching In
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I did look at the wires and they look good. I mean they aren't close to anything that will rub. They are also covered with that plastic flex tubing. The only thing I can think is a bad battery. I mean there is nothing else that could cause the alternator to go bad except the battery or these main big wires right? Thanks again buddy
Pretty much....unless you keep getting junk alternators. We had a car in the shop yesturday with a bad alternator. We put a brand new delco on, came back today with another fried alternator....battery tests good. Just a junk alternator out of the box.
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Oh well I will check the battery, wires, replace the alternator and test again tomorrow. Do you need to fully charge the battery before starting the car? Some people say that if you don't fully charge the battery you are forcing the alternator too much and it burns it down? Is this true? ( i don't think so but im not an expert)
From my experience, it makes no difference on how low the voltage is when the car is started. A good alternator will charge it right back up in 20 minutes.
I would check all the cables, voltage drop on all the cables and test the alternator on a bench tester before installing it in your car.
Yet, I have still seen numbers of posts on here with alternators dying from high RPM.
If I had to get an alternator I would probably go with a high amp rebuild or a after market. The only down side is that they are more expensive than the usual parts palace remans.
I would check all the cables, voltage drop on all the cables and test the alternator on a bench tester before installing it in your car.
Yet, I have still seen numbers of posts on here with alternators dying from high RPM.
If I had to get an alternator I would probably go with a high amp rebuild or a after market. The only down side is that they are more expensive than the usual parts palace remans.
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Well this what I did. I got another replacement alternator. They didn't have the new one in stock. I put the alternator in. Before I decided to test it I checked all the major electrical wires. The starter wire that comes from the battery didn't look too good. It was overheated and had some spots that were corroded. At this point I started thinking that these wires are 10 yrs old and need to be replaced. So I bought new wire and changed the starter wire, the alternator wire and the engine fuse box wire. I increase the wire size to a #4 wire. Not only the alternator problem got solved but also my low voltage problem. I used to only get around 12.8 - 13.4 volts. Now I get 14 - 14.2 volts all the time. Either the wires were creating alot of resistance or the alternator was a crappy one. Thanks for the replies.
Well this what I did. I got another replacement alternator. They didn't have the new one in stock. I put the alternator in. Before I decided to test it I checked all the major electrical wires. The starter wire that comes from the battery didn't look too good. It was overheated and had some spots that were corroded. At this point I started thinking that these wires are 10 yrs old and need to be replaced. So I bought new wire and changed the starter wire, the alternator wire and the engine fuse box wire. I increase the wire size to a #4 wire. Not only the alternator problem got solved but also my low voltage problem. I used to only get around 12.8 - 13.4 volts. Now I get 14 - 14.2 volts all the time. Either the wires were creating alot of resistance or the alternator was a crappy one. Thanks for the replies.
I ran 0/1 on all the crap in my car.
My voltage used to go down when I turned on the accs like AC and headlights. Now it actually increases!!
I will upgrade the wiring in all my cars from now on.
