As far as i remember my car used to run at ~13.9-14.5 at idle now at times will will only run at like 9-10.5v at idle. This will cause all the lights to dim and the engine to go kinda slugish but as soon as i rev it the voltage returns to it normal 13.9-14.5. If the Alt never went to to full charging i would guess that would be the problem but it do so does anyone have any ideas? All these numbers are gotten from my PFC and not waring lights on the dash come on. In the FSM they suggest testing the plug terminals, is it fine to unplug the grey connector while the car is running?

Thanks
~Luke

 

Test the alternator, if it's not that, then I would look into the grounds, and make sure they're all making good contact.

 

check the belt tension

 

A good battery (a fully-charged one in good enough shape to start the car) should be able to maintain over 10 volts for a short time at idle, even if the alternator is weak or not capable of handling the load at low RPM. Therefore, I would suspect bad wiring or connectors from the battery to the circuits (other than the starter circuit, since you did not mention a starting problem).

 

I had the Alt tested and it puts out 4.2 volts so i'll trying some of the other things.

 

I just put it back in and now it works, i'm guessing is was like mad 7tist, the belt tension.