my car is weird, the voltometer usually rides between 14.7 and 15.1 stock but occasionaly it will plumit while driving or sitting at a light down to the lowest of 11.2 and then come back to 14.7 but it usually happens at night and dims the lights to the point where i really cant see any thing any tips or suggestions greatly appreciated

There are some testing procedures in the tech info area for the charging system and cables. Give those a try. Also make sure all cables are clean.

tried em it checks out good still stumped

ZZ performance makes a voltage booster, it'* a simple plug in. That might help.

ya im ordering one from 3800 performance will come in handy for the upgrades i want to do also

mine does the exact same thing. my 93 did it as well. and my dads 05 grand prix did it too. i read a tsb written for the grand prix that explained the whole problem and how the alternator cant put out that much voltage while alot of accessories are on at idle. that why if u bring the rpms up the voltage goes up to normal as well.

My GXP has been doing it since it was new (now at 70,000+).
Real noticeable at night when the lights dim. Voltage drops waaay down. Lasts about a second.
Mine happens at all speeds up to 70.
I haven't seen any satisfactory answer or solution yet.
I'm convinced that something with a high draw kicks in. Air pump?

my air pump has not come on before or during so i dont think it would be that when it does kick on there is only a .1 change in the voltometer

wow u have an air pump?? i dont have one of those.