12.5-12.9 volt reading?
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Where are you getting this reading from? If you're reading ignition voltage with a scanner via the PCM, it's going to be lower than what you'd see at the battery with a multi-meter. With the load of the A/C compressor, high speed cooling fans and the blower motor, all running at idle (especially if it's an A4 with it's lower idle speed), depending on where that reading is coming from it may or may not concern me.
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If the truck alternator was required for adequate charging with a stock electrical load, stock wiring and good ground contacts, then none of these cars would have ever charged properly from the moment they came off the assembly line.
All the pimping of truck alternators, as the cure for all charging system issues with stock electrical loads, leads me to believe that my four LS1 F-bodies must've been the only ones in history to leave the factory with working charging systems in stock form.
All the pimping of truck alternators, as the cure for all charging system issues with stock electrical loads, leads me to believe that my four LS1 F-bodies must've been the only ones in history to leave the factory with working charging systems in stock form.
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my gauge must be off because when hot at idle it right at the red line , but if i check the battery with my meter 13.5 on the dot, and the car has white face gauges . Is 13.5 good at idle when hot with stuff running. ?
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I'd also add that GM would have recalled these cars if the stock charging system was deficient.
For the OP - you are normal! 13.2 Volts is the theoretical perfect battery voltage. As long as you don't drop below 12 with the headlights on and the A/C on, all is well.
The red lines are on the gauge for a reason. As long as you aren't close to them and are using the car for stock purposes, you are fine.
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I once heard that pimpin ain't easy... ![](https://encrypted-tbn2.google.com/images?q=tbn:ANd9GcRGWQvww2u9eQ8UBV4o8ewEqWnlCXz7iZ0G4V8dvabqqEWvxesd)
I'd also add that GM would have recalled these cars if the stock charging system was deficient.
For the OP - you are normal! 13.2 Volts is the theoretical perfect battery voltage. As long as you don't drop below 12 with the headlights on and the A/C on, all is well.
The red lines are on the gauge for a reason. As long as you aren't close to them and are using the car for stock purposes, you are fine.
I'd also add that GM would have recalled these cars if the stock charging system was deficient.
For the OP - you are normal! 13.2 Volts is the theoretical perfect battery voltage. As long as you don't drop below 12 with the headlights on and the A/C on, all is well.
The red lines are on the gauge for a reason. As long as you aren't close to them and are using the car for stock purposes, you are fine.
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...same issue here folks... My 02 WS6 battery is draining....Had the alt tested with the car on idle and it read 12.92.... I drove it home(5minutes) and my check gauges light came on and I noticed the batter running low again?.... so Do I need to get under my car and replace the Alternator?