Topic: fuel pump problem need help

[yotatruck]

i got a 89 toy it just shut down one day like u cut the key of no warning at all i check the plugs geting good fire no fuel changed the filter and fuel pump but i am geting no power to the pump i wire it strait it will run fine at idle when u drive it blows fuse under the hood i looked for a cut wire or short found nun i dont have a clue maybe the computer or a sensor ?

[BLACKDOG]

What fuse are you blowing?  the EFI fuse?  I had a similar issue, and it turned out that the O2 sensor wires had gotten too close to the Cat, burning through the casing and shorting the wires out against each other.  This was causing the EFI fuse (not the relay, the 15amp fuse)  to blow, killing the truck. 

[*ROKTOY*]

Check your circuit open relay.

[yotatruck [OP]]

circuit open relay is good i bought a new one i will check thr o2 wires yes it is the 15amp fues that is blowing

[BLACKDOG]

circuit open relay is good i bought a new one i will check thr o2 wires yes it is the 15amp fues that is blowing

yeah, check those wires.  when I swapped my stock crossmember out for the marlin one, I ziptied the wires up since using the marlin crossmember eliminates the little plastic clip holding those wires.  I didn't route them far enough away from the cat ( I also had an exhaust leak blowing right onto them, wich prolly didn't help)  and they just cooked

[yotatruck [OP]]

hey blackdog the o2 wires was melted almoast in 2 that was the problem thanks i was ready to pull my hair out

[speedemon]

mine did the same thing this weekend on a wheeling trip.  i didn't check the o2 sensor wires but that is the first thing i will check.  my efi relay was hot as hell and it kept blowing that fuse.

Trail fix:  I am running a msd fuel pump with a fuel cell so i ended up cutting the wires to the fuel pump and wiring it directly to the battery with a switch.  this worked for a while, but now the fuel pump will run, it will crank, but won't start.  i didn't get to check to see if it had fire, but i don't think that is the problem.  any ideas?