I have noticed latley when my truck sits for a week or so and I start it the "check guage" light comes on and the voltage guage is lower than it should be. It doesnt happen everytime either. Once I hit the gas the guages jumps up and the "check guage" light goes away. I have had an underdrive pulley on for a few months but I did recently install a jtvsp throttle body. The idle does not seem low but could the throttle body messed with the idle just enough for it get mad? Is this a product of the underdrive pulley? I have noticed since the underdrive pulley the belt will squeal for about one second after starting sometimes. If this is check guage voltage issue is not a big deal I wont sweat it because it only does it sometimes and disapears once you tap the gas. Just want to make sure.
The battery is about 6 months old and the Belt came with the new UD pulley. There is a chance that this is happening only after it rains. I know that hood scoop funnels water on the front of the engine. Maybe the belt is slipping slightly until it dries itself.
Yes happens to me. I live in wa it rains alot so when my truck sits outside the belt gets wet and slips. Ya engine light comes on then back off once the belt stops slipping
My issue was resolved after my crank pulley removed itself from the crank shaft and when I replaced the pulley.
Have someone start it while you watch everything. See if you see a pulley that doesn't initially spin. Idler and tensioner pulley are common to lock up. Correct belt size for Pulley would be next question. Remove belt and spin all accessories listening and feeling for noise/roughness