The EFI fuse [15A] keeps burning; I replaced with a 30A fuse and it ran for 300 miles before burning 2 more 30A fuses in 2 miles. Today, just for the fun of it, I put a 15A fuse and the truck ran for 30 miles before burning again. Any ideas, please?

 

Common cause is an O2 sensor wire that has burned insulation from contact with the hot exhaust, causing a short.

 

Thanks for such a quick answer; I will check the O2 sensor first thing in the morning.

 

I would also say the o2 wire . I learned the hard way after being stuck on the highway and 600$ later they still could not fix it.. but thanks to google phones and this site i fixed it for $ 0.32 in a parkinglot

 

Smarvin,
Thanks a lot for your input; now I believe my problem is bigger: before, if I did not have a fuse on hand I was able to "bridge" the two ends on the fuse slot but now, even putting together those two ends [that I plucked from the fuse box] the truck would not start. Any ideas at least to get it moving to take it to the shop, please?

 

Look under the truck for sure ! check the o2 sensor wire for being melted

 

Thanks Scott; I will go under it.
Walter