Woundering if something is wrong. When I start my 96 ram diesel 2500, The battery gage needle in a second starts to move to right of center on the gage and then back down a little to the left of center then back up again a little to the right of center mark. This gos on for a while as I am Idling. When I start driving, after a few seconds the needle stops doing that and stays to the right of center like It is supposed to. Also, when the needle is moving back and forth like above I can hear the motor go down just a little, and the dome light dims a little. Is this do to the engine heater warming the fuel up or whats going on? Thanks, Jim

 

Go to Performance and Accessories for 2nd Gen. Rams....there is a long thread about it for you. It's "stuck" at the top for all to see.

https://www.dieseltruckresource.com/...ad.php?t=57485

Long story short though, it is your grid heaters warming the incoming air for your truck cycling on and off.

 

I actually read through the owners manual for my 99 and it mentions it in there.

 

Its just your grid heater, my 95 does the same thing

 

I had the same question about my 02 and depending on the outside temp it does it any where from about 2 minutes to 5 minutes then levels out.