Quote Originally Posted by Abgunnar View Post
Mine does it also it’s the grid heater pulling the voltage down if you watch as soon as voltage goes back up the truck smoths out.

If you disconnect hot wire to the relay for grid heater and start it I bet there won’t be surging I’ve tried it.
Well you gave me one more tally mark to on the side of why I should do a grid heater delete here soon.

Good info!