Need help. For the last 2 winters, when it gets to around 30 F, my battery won't charge. If I let the truck warm up for a bit, then my voltage will jump upto around 14v where it should be. Until then, the truck is just running off of the battery. The colder it is, the longer it takes to "kick" in. It's just a standard 3 wire Delphi 105 amp. Any ideas? Bad alternator or something else?

 

Sounds like the voltage regulator inside the alternator. Have you used the truck to jump start another vehicle lately?

 

No I hadn't used to jump anything else. I kind of was thinking the same thing with the regulator, so I threw on a used one I got cheap with 30K, it was fine this morning and it was about 15F out. Hopefully problem is solved.

 

i might be having a similar problem...its gotten pretty cold in texas the past week or so and my truck has had about 5 starts that were really rough sounding...