Question about 1989 Pontiac Firebird

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Bad alternator? Or Bad Mechanics?

I got a new battery installed and the voltage meter was still low. I showed my mechanic and he said let it run for a half hour or more, it shouldgo back up. I did what he told me and then I took it to school, and on my way back it started to get dark, so i turned on my headlights and thats when all the problems started. My instrument panel looked like a xmas tree and everything was going out of wack even my rpm meter was moving up and down like crazy. When I had to come to a stop because of traffic the car finally died and i had to get a jump. I made it home and it ended up dieing again in the driveway. Shole I find new mechanics or is this either an alternator, battery cables corroded, or a sensor problem? Please help me!!

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  • vumbooco22 Dec 11, 2008

    Would that explain the Rpms bouncing up and down rapidly too. Or should I buy a new voltage regulator first. When I turned the lights on the battery meter in my truck kept gettign lower and lower, and they were't bright at all. even my hazard flashers weren't working. I thank you for your response tho. Im debating what to get first an alternator or voltage regulator.



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A wise man onceshowed that when your regulator is faulty you'll often find your battery looks wet, from the acid boiling over, i was able to disconnect it and clean conecters to prolong it use for a tempory fix, its a whole cheaper to replace then your alternator if your unsure

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Hi if the battery is showing no charge on a voltage metre (usually around 13.5) and putting the lights on drains it than i would go for the alternator but first check the belt is not too loose, A little tip>>>> let the car idle and turn the lights on, then rev the car and if the lights dont brighten up then the alternator is not throwing out a charge, Hope this helps

Posted on Dec 11, 2008

  • usersteve83 Dec 11, 2008

    Hi it would do all sorts to the electrics, when you put you lights on and they are very dim rev the engine and see if they brighten up if they dont than it will be the alternator or the alternator belt (check the condition of the belt) but it is most likley the alternator,
    regards, Steve



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