fuel and spark problems

[projectAtoB]

ok so first off the starter hung on my 86 bronco II. its nothing but a 400 dollar play toy, so for a couple of days i simply took the starter wire off of the starter solenoid and was toching the wire to the post when i wanted to start it. i know thats stupid and not good for anything but its a 400 dollar truck so spare me. anyways someone else tried to start the truck and touched the starter wire to the wrong post of the starter solenoid. it burnt alot of fuses, screwed the starter solenoid, the batery, and the fuel relay i replaced the battery it was under waranty new solenoid and fixed blown fuseable links. and fuel pump relay. now first off i noticed the pump wasnt coming on when i turned the key on. that was first prob. there are 4 wires on the relay a power wire coming from the starter solenoid, wire going to the inertia switch(which has already been cut out) and a smaller gauge wire and a red wire. i can apply 12 volts to the wire going to the inertia switch and the pump cuts on. but the smaller wire which i am guessing its the trigger wire for the solenoid has no power on it( I know its momentary when u cut the switch on) so i was going to put a switch on the pump to cut it on(remember its a beater truck) i wanted to make sure it was gonna work so i applied 12 volts to the relay again cut the pumps on and tried to crank it. thats when i realized i had no spark. very long story short, is this pointing towards the computer is bad? very sorry about the long post im just stumped here.

 

[holyford86]

its possible, if you are getting power to the computer and it isn't kicking the pumps on, or throwing any spark.

 

[Psychopete]

its possible, if you are getting power to the computer and it isn't kicking the pumps on, or throwing any spark.

+1, start with checking out the computer relay and make sure that pin #1 (larger yellow wire) has positive 12 volts. Can you hear the relays clicking? +1 to checking for spark. A wiring diagram will be your best friend on this one IMO. It's easier to read the diagram and understand the circuit than it is trying to understand someone trying to explain it to you in words. If you do have power at pin #1, you might start at the computer relay and work your way from there.

Bottom line is if the computer is not functioning (not powered or fried), you simply won't have fuel pump operation (or spark for that matter).

Pete

 

[projectAtoB]

well the ecu relay was blown replaced that and got the spark back but still no fuel pump. after the ecu relay was replaced i found that if i apply a ground to the switch wire on the fuel pump relay that the pumps would come on. tried to find where i was loosing a ground and never could so i just added picked up a ground from the wiring outside and switched it inside the pump works now. i give up tryin to fix it right. thanks for the help

 

[smokeymcpot]

what and where is the ecu relay? i'm having a similar problem; need spark and have tried quite a few things already.