TurboMinivan
Still plays with cars
- Location
- Lehi, UT
I headed out to run the Snakes today, but I didn't make it there. Heading up the hill just after Chevron, my Suburban's voltage began dropping and fluctuating, which tripped the low voltage warning light. The gauge needle was down to around 11 volts, and it was jerking back and forth slightly. Not having a great place to stop right there, I continued on to the top of the hill, then pulled over to take a look underhood.
As I was pulling over, the gauge returned to normal and the voltage warning light turned off. Hmm. I went ahead and shut down, then lifted the hood. All the obvious stuff seemed fine--no loose wires, no serpentine belt issues, etc. As I restarted the engine, the gauge sat right at its usual 14.5v reading, seeming as if nothing had ever been amiss. With the trans still in Park, I tried revving the engine. As I would hit/crest 2500 rpm, the gauge would suddenly drop and do its erratic behavior thing. When I let the revs drop below that point, the voltage went back to 14.5 and everything went back to normal.
I decided not to continue the trip. Why risk a total break down half an hour away when my house is only three miles behind me? So I tucked my tail between my legs and headed home. I kept a very close eye on it for this return trip, and the pattern continued: rev to 2500+ and things went to hell; drop below 2400 rpm and everything was perfect.
After I unloaded and unhooked the trailer, I decided to go for one short drive around the block just to confirm the symptoms. I wanted to see if anything changed (a) without the trailer attached or (b) without the A/C running. But even with those variables eliminated, the 2500 rpm pattern continued.
I'm guessing this is an alternator issue. Does anybody know if the Suburban's voltage regulation is internal to the alternator? I hope it isn't controlled by a computer.
Any help you guys could provide would be very... helpful.
As I was pulling over, the gauge returned to normal and the voltage warning light turned off. Hmm. I went ahead and shut down, then lifted the hood. All the obvious stuff seemed fine--no loose wires, no serpentine belt issues, etc. As I restarted the engine, the gauge sat right at its usual 14.5v reading, seeming as if nothing had ever been amiss. With the trans still in Park, I tried revving the engine. As I would hit/crest 2500 rpm, the gauge would suddenly drop and do its erratic behavior thing. When I let the revs drop below that point, the voltage went back to 14.5 and everything went back to normal.
I decided not to continue the trip. Why risk a total break down half an hour away when my house is only three miles behind me? So I tucked my tail between my legs and headed home. I kept a very close eye on it for this return trip, and the pattern continued: rev to 2500+ and things went to hell; drop below 2400 rpm and everything was perfect.
After I unloaded and unhooked the trailer, I decided to go for one short drive around the block just to confirm the symptoms. I wanted to see if anything changed (a) without the trailer attached or (b) without the A/C running. But even with those variables eliminated, the 2500 rpm pattern continued.
I'm guessing this is an alternator issue. Does anybody know if the Suburban's voltage regulation is internal to the alternator? I hope it isn't controlled by a computer.
Any help you guys could provide would be very... helpful.
