my 87 F-150 I-6 4 SPD granny 4X4 won't start.it will turn over but not start.i don't hear the fuel pumps energize or even hear the relays energize.do relays go bad and how do i check them?

 

First check the small black wire with a green stripe leaving the NEG (-) post of the battery and make sure it has a good ground. Also check the wire going to the Body (not frame) ground.

If they are OK then put you hands on the EEC Power relay and the fuel pump relay and have someone turn the key just to on.
Did both relays click when the key was turned on?
If not check the wiring under the relay sockets.
If OK check out the Ignition switch.
If not replace the relays and sockets.

If the relays did click did the fuel pump relay (the green socket one) click again one second later when it dropped back out?
If it did try pushing down on the reset button on top of the Inertia fuel shut off switch.
If the Inertia fuel shut off switch was OK check for power for one second at the Inertia fuel shut off switch wires (in & out) when the key is just turned to on with a test light.

Let us know what you find at this point.

The diagram below shows both the factory relays and the replacement relay wiring if you need to replace them. The numbers in the relays in the wiring are for the replacement newer stile relays.


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i checked the relays,and they both click.how do i check the ignition? the inertia switch button is pushed in, i checked power at the connector, got nothing.now what? thanks for the info.

 

the fuel relay only clicked once.i didn't hear the fuel pumps (any) energize.

 

fusible link "M"???
The yellow wire in the above schematic provides power -through- the relay but does not provide the pull down current.
It would click, but do nothing if the link was burnt coming from the starter solenoid.

 

the truck turns over,but doesn't start.i'm getting spark but no start.it leaves the fuel system.i'm not a mech. but like to tinker alittle.the truck is not my daily driver,but like to drive it a few times a month.

 

Will it fire on ether?

 

Does the fuel pump relay socket have power coming to the yellow wire?

 

i'll have to check that out when i get home from work today.

 

i just remembered,yes power is at the yellow wire of the fuel relay.but i'm not getting power at the anertia switch when key is on or in start position

 

I'm not the expert here but it looks like there are two connectors in the brown wire from the fuel relay to the inertia switch.
If you have one second of power at pin 87 (coming out of the relay) then I would suggest you trace this wire and check for loose or corroded connections.

 

thanks i'll try that.

 

i'm not getting power at pin 87,doesn't that mean the relay is bad?

 

Yes.
If you have power at 30 and no power at 87 when it clicks then replace the relay.

 

thanks for the info,i'll replace the relay.