Volt meter??

[Motorboy8769]

The volt meter swings back and forth like something is drawing. Ton of power for 2 seconds and then back to the middle what could this be??


Sent from my Autoguide iPhone app

[madpogue]

Weak batteries, perhaps. Glow plug relay closes, voltage drops, not enough voltage for the relay to hold, it opens again, battery voltage recovers, enough to close the relay again, voltage drops again, rinse, repeat. Is this with the key in RUN, engine off, or after it's started? Any trouble starting?

[Motorboy8769]

This is after running and no problems starting it does smoke until warmed up according to my dad it's his truck just trying to help him it also has over 300k

[ianstew]

id bet the voltagae regulator in the alternator is shot. mine did the same thing. replaced alternator, all was well