OK, I am confused need some help with this one. Recently my truck has had problems starting in the morning since it has cooled down during the night. I am runnning a fass pump and it is load, if I knew how load it was it would still be on the shelf. Anyways I can here the pump rev up and down and the lights flicker, I assume the heating grid is cycling. The battery guage shows about 12volts approx on the dash. Once I drive for a while the voltage guage will come up to approx 16? I am assume there is a temp switch someplace telling the computer to turn the grid off once a certain temp is reached.
I am puzzled because I got home today, the engine was warm. I turned my truck off and fired it back up and the pump rev up and down and the voltage guage was at 12?
I have ordered a new preheat coil, wondering if its cycling more oftan and drawing my current because its toast? Wondering if anyone else has experienced this problem and what to do. Hardly seems normal?
Thanks

My truck is stock, expect for the pump.

 

My truck does the same thing on occasion, as did my last truck. I would assume it is fine all the dodges seem to do it more or less when the engine is started. Mine will do it when the engine is warm sometimes but doesn't do it for as long.

You should also fill in your Sig so we know about you truck...???

 

Thanks for writting back Rollin Coal, ya guess those heaters are drawing a ton on juice. Still trying to trace the bad starting problem, there is a post about a FCM.
I would fill out my sig, not sure how?
Thanks