dont hear fuel pump
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Junior User
Joined: Jan 2004
Posts: 66
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dont hear fuel pump
i got a 1986 ranger 2.9 auto 4x4 i went to start it and it would only crank. i didnt hear the fuel pump kick on. ive replaced the relay, the high pressure pump. still nothing. if i put direct power to the pump for a second it works fine. i also put a jumper wire between the wires at the inertia switch. what else should i be looking at? is there a fuse im missing? thanks in advance
Senior User
Joined: Dec 2005
Posts: 253
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From: Beaver, Pennsylvania
Check too see if you have power to the relay, Not sure what wire to check but 1 should be hot with key on. If there is power there I have had wires in the harness corrode and break, you may have to run a new wire too the pump
Senior User
Joined: Dec 2005
Posts: 253
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From: Beaver, Pennsylvania
I don't have a wiring diagram handy, but if you take a jumper wire from the hot too 1 of the other posts { not sure witch 1 } the pump should run. But I really suggest a wiring diagram too do this.
Postmaster
Joined: Oct 2003
Posts: 4,516
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From: SoCal
Originally Posted by openscars
theres a yellow wire that has constant power but im not sure what the others are supposed to have
At the relay red should have 12 volts with key on.
When you turn the key to run orange/light blue should have voltage for 2 seconds.
Check for that 12 volts at the inertia switch on orange/light blue.
Postmaster
Joined: Oct 2003
Posts: 4,516
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From: SoCal
FIrst thing you need to do is figure out if the problem is on the relay or fuel pump side of the inertia switch.
Connect your voltmeter to orange/light blue at the inertia switch & turn the key to run.
Do you see 12 volts for 2 seconds??
Connect your voltmeter to orange/light blue at the inertia switch & turn the key to run.
Do you see 12 volts for 2 seconds??
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Postmaster
Joined: Oct 2003
Posts: 4,516
Likes: 1
From: SoCal
BTW, like rags said you CAN jump 2 wires at the pump relay: yellow to orange/light blue and the pumps should run with the key on or off.
ALL the wires in your truck have smoke inside them. It's the smoke that makes them work, so be careful that you dont let the smoke out.
ALL the wires in your truck have smoke inside them. It's the smoke that makes them work, so be careful that you dont let the smoke out.
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Postmaster
Joined: Oct 2003
Posts: 4,516
Likes: 1
From: SoCal
Since pumps dont run & theres no spark it's souding like the ignition switch might be shot.
The ignition switch sends voltage to the ignition coil/main relay/& idiot lights on the dash etc.
Are the idiot lights working when you turn the key?
The ignition switch sends voltage to the ignition coil/main relay/& idiot lights on the dash etc.
Are the idiot lights working when you turn the key?
Postmaster
Joined: Oct 2003
Posts: 4,516
Likes: 1
From: SoCal
Originally Posted by openscars
i see the battery light turning on
Try this, turn the key on & check for 12 volts on the red wire at the fuel pump relay.
If it's not there check voltage on the red wire at the EEC relay. If theres no voltage there either, replace the relay & see if this thing will fire up.
The red wire from the EEC relay splices all over the place and provides voltage to the fuel pump relay/computer/injectors etc etc.