Once in a while when i drive my 1996 Lumina Mini Van, i am getting voltage surges which causes a couple of my Gages lights to come on, plus at night i notice that my lights dime going bright when the battery Gage spikes up to the plus 18 in the red zone or going dime, it causes the Air Bag led to come on and sometimes the Anti-Lock break light to come on, but it is NOT an anti-lock problem, nor and Air Bag Issue, sometimes effect the acceleration when starting up from a stop, i actually have to turn off the van for about 120 seconds and then were good to go, other times it just clears by itself, this happens very intermittent and can go for a day or two without issue, however, when i am driving, it does not effect me when i am driving normally even when this fluctuation happens in voltage. Is this an early indication of my starter motor going bad, or my Alternator not regulating voltage properly. Please Note: The Battery Gage is not steady it rides between middle and up to the first indicator most of the time, only sometimes does the meteor go into the red zone which causes the Gage LED's to come on, mostly if it does not hit into the red zone where it show (18) but close to it, only the Air Bag LED goes on, the Head Lights when on at night, you can see the dash lights and head lights dimming and going bright when it shoots into the red zone. Any ideas on what it can be, I checked all wiring within the engine, and put the tester on it and it found all systems are normal, there was no code displayed, however, it was not spiking into the red, i may have to wait again when it does it. I have heard that a Starter Motor can do this in its early stages of failing.
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1996 Chevrolet Lumina APV
Question: Voltage Spikes - very intermittantly
Answer #1bluefire December 09, 2009, 18:30Rookie
if your abs light is coming on you could have a wheel speed sensor going bad or a Hydraulic Modulator solenoid or motor pack it could any one of these so try pulling a code from the electronic brake control module. and also check your engine ground wires. and also last but not least your generator output check it at the battery posts it should be between 13.2 to 15.2 with your lights, wipers, air conditioning , on high, all turned on.
Answer #2mahindra December 09, 2009, 20:25Journeyman
How do you know you hit "plus 18" volts. If you did and you continue to drive this van you'll be replacing a PCM and other things!
Replycbcs, December 10, 2009, 06:39Rookie
I just checked all the logs and it looks like it may be a bad regulator within the Alternator, if your voltage is riding on the high end or if it starts going into the high end and spikes into the red zone causing these LED's to light up, your PCM is bad or going bad within the Alternator and needs to be rebuilt or replaced as soon as possible. The voltage regulator is intermittent or has failed. Charging system voltage is controlled by the Power Train Control Module (PCM). In this case the alternator will need to be replaced or rebuilt.