My ECMB or fuel pump fuse will blow every time I'm in gear and accelerate quickly. But if I'm in park I can floor the pedal and the fuse won't blow. Only while I'm in drive. I just put in a new fuel pump and fuel fliter after this problem started.

 

Sounds like you could have a wire being pinched by something when you accelerate hard.

 

But it only does this when the truck is in drive?

 

The problem that I'm having is the ECMB fuse blowing when I accelerate fast in gear. When it's in park or neutral I can rev the gas as much as I want with out it blowing.

 

i had this exact problem myself, a few different things led to it though.It started back when my tranny mount went out, it got to the point when i accelerated hard at all i would blow an instrument/gauges fuse.all my gauges zero;ed out even the speedo,it also effected the shifting i had to manually shift it or it would try to start out in d and create a horrible drag.After geting the tranny mount fixed i never lost that fuse again.but then the ecm 1 i think it was,(i believe theres 2)would blow when i shifted it into drive but usually not till i was warmed up 10-15 minutes.It could sit idle for hours np.my mechanic pulled his hair out trying to figure it out,he finially found the bad wire/s in the wiring harness i think he said where it passes through the fire wall not fare from the ecm.Replaced my wiring harness and i have no problems now.we had determined the movement from the bad tranny mount caused this problem but i have no idea really just glad its fixed lol

 

Thanks I will check that out, because now when I turn the key the fuse will blow right away. and this is with a 30 amp fuse in the ECMB

 

Hey! Did you ever get this thing figured out? I am having a VERY similar problem.

 

Check the fuel pump test lead. It hangs out of the wiring harness up on the firewall near the tranny dipstick. Mine was hanging out so far it touched the tranny dipstick tube, shorted to ground, and blew the ECM-B fuse. I capped the wire off, and tied it up - no more blown ECM-B fuse.