So trying to narrow down a new issue with my Buick. The lights seem to pulse dim and back to full brightness every few seconds when cold started but only when it's really cold outside. Seems to be fine above freezing but below 20F it will pulse every light including interior lights, headlights and dash and the voltage moves around slightly on my voltmeter but hard to say how much because it's only been this cold a few times.
Also the Blower motor noticeably loses speed during the dim pulses as if you turned the speed down.
Also sometimes if I turn the Blower on high and turn the rear defroster on my voltage plunges pretty bad or bounces too.
It seems to stop if I turn the rear defroster off. Kind of two separate issues maybe?
I have even noticed it sometimes when slowing for a turn when the engine falls to idle speed mid turn the voltage drops to the 12v range as if I'm running on battery only but as soon as I tap the gas it comes right back up into the middle or high 13v range.
The issues with pulsing pretty much disappears within 5 to 10 minutes of driving. But the voltage dips on turns are harder to re create.
My alternator is a recent replacement, it's a Tough one new unit aka Remy. I am not sure it's the alternator but am leaning towards a bad body ground? The alternator puts out plenty of voltage if you don't look at the isolated incidents. If it's really cold outside it will put out right at 15v, usually high 13s no problem when warmed up.
Battery is a autocraft gold about 2 years old tested good somewhat recently. I even fully charged the battery the other night inside on my diehard dh15a automatic charger and it still pulsed at full charge as it was about 20 degrees outside, so I don't think the battery is the culprit.
It's going to be pretty cold tonight when I leave work so hoping to see what happens when I first start it tonight and to pay closer attention to the voltage.
Any leads would be appreciated.
Also the Blower motor noticeably loses speed during the dim pulses as if you turned the speed down.
Also sometimes if I turn the Blower on high and turn the rear defroster on my voltage plunges pretty bad or bounces too.
It seems to stop if I turn the rear defroster off. Kind of two separate issues maybe?
I have even noticed it sometimes when slowing for a turn when the engine falls to idle speed mid turn the voltage drops to the 12v range as if I'm running on battery only but as soon as I tap the gas it comes right back up into the middle or high 13v range.
The issues with pulsing pretty much disappears within 5 to 10 minutes of driving. But the voltage dips on turns are harder to re create.
My alternator is a recent replacement, it's a Tough one new unit aka Remy. I am not sure it's the alternator but am leaning towards a bad body ground? The alternator puts out plenty of voltage if you don't look at the isolated incidents. If it's really cold outside it will put out right at 15v, usually high 13s no problem when warmed up.
Battery is a autocraft gold about 2 years old tested good somewhat recently. I even fully charged the battery the other night inside on my diehard dh15a automatic charger and it still pulsed at full charge as it was about 20 degrees outside, so I don't think the battery is the culprit.
It's going to be pretty cold tonight when I leave work so hoping to see what happens when I first start it tonight and to pay closer attention to the voltage.
Any leads would be appreciated.
