can a 50a fuse replace a 40a fuse for ignition?

 

yes mine poppes from time to time. i am still tracking down why it does it. but thTs whT i do to get home is swap over the "lights" 40a fuse

 

h22eg2, these are the most common ignition shorts I find:
improper aftermarket alarm/gauge splices
improper killswitch splices or low switch rating
corroded/incomplete chassis grounds
improper wire tuck, loose EC fuse box or bouncing battery
loose plug at under-dash fuse box
water leakage

 

well NON of those fit my problem as i have

NO alarm/kill switches
reduntent chassis/engine grounds
have check ALL fuses at BOTH fuse boxs and have no amp/volt drop or spike with GOOD wiggle test
NO water leaks
No loose battery (relocated and double straped)

my honest thinking is i have a wire shorting to power addig amp draw. it is VERY ht and miss. only done it 2 times in VERY diff situations.

 

monitor current, then try to simulate a short and monitor current again. the more nodes you monitor, the closer you'll get to the problem node.