Luder[PAK9]

I have a weird voltage dropoff issue. At random times, anywhere from 3 times a minute to once every 5 minutes, my voltage guage dips down to 13 volts and all the electrics dim and the heater blower slows down. Voltage then immediately returns to normal (between 14-15.5v on the dash guage). Sorta like someone used a dimmer switch on the car to bring it down to 50% and then brought it right back up.

I don't really notice this problem at highways speeds, only at 40 mph and below. It happens whether I'm at idle or at light throttle. I also don't notice anything odd with the engine when this happens (stumble, misfire, etc).

Battery and belts are new.

Any ideas? (Please don't say I have to shell out $180 for a new alt--I just bought this car )

haacer

iTrader: (1)

You need to know if your alternator is charging consistently. An electric shop should be able to handle this. It could be an alternator or something loose.

If the vehicle isn't doing this while idling, I would suspect a loose connection. Check for tight clean connections from the battery terminals to the starter and ground points.

thaigleshmk

Hm. mine is doing the same thing when it's cold/first start in the morning
but once it's warmed up it's fine

Rob Hood

I'm having the same problem on my truck - https://ls1tech.com/forums/general-maintenance-repairs/827097-electrical-system-problem.html. I don't remember when it started, but it's had this issue for quite some time.

TheLS1Kid

iTrader: (12)

Do the rpm's drop?

Get your alt checked at autozone or advance auto.

Rob Hood

In my case, I'm not so sure, but I think yes, based on the sound. This typically occurs after mild acceleration and lifting off the throttle in preparation to stop the vehicle. If it occurs at night, the headlights, dim, the volt gage drops below neutral or charging, then the system quickly resumes charging and the lights return to normal illumination.

Alt

iTrader: (6)

Guess I need a new alt too then. I've been having a similar issue along with the voltage reg going nuts every once and a while. The pulsing I could deal with but the drop after I let off the gas around 30mph was starting to scare me a little.