Fuel Related Issue. (Maybe Relay?)

[2tonebrown1986b2]

Hi there, thank you in advance for taking a look at this thread.

I own a 1986 Bronco 2 (V6 4WD), 2.9L Cologne.

Let me start with some history to help explain the situation im in..

Last year, ran into one problem after the next, in the following order (this starts in June of 2011 - October 2011) Alternator.. Power Stearing Belt, Alternator Belt, Ignition Coil, Spark Plugs, Distributor Cap, Ignition Module, Starter, Fuel Pump Replaced. The Fuel Pump was the only part i was not comfortable replacing and due to the situation i was in, i was pressed on time, so i took it to the nearby ford dealer ship :/ didn't get raped too bad, However. Now for the situation im in.. Assuming its the Fuel Pump, it's still under warranty from the shop that replaced it. So i would love to take advantage of that.

However before i send it in (IF i cant fix it myself) I want to troubleshoot to make sure it's nothing else but the fuel pump.

Currently Bronco Won't Start, It Turns. Try's but nothing.

I do hear a click when i turn the ignition to the point where the fuel pump usually has a short quick buzz to let me know it's pressurized. So it's obviously not pressurizing, however the fact that the relay is making any sound at all should show it's ok? This is what im un sure of. How should i go about testing this relay, what do you think?

Thank you again for taking the time to read this. I'm no mechanic, however i love working on my bronco and learning how to work on it/troubleshoot it. I've done all repairs to this bronco except replacing the fuel pump. I still have a lot to learn.

 

[Earl43P]

This is easy, assuming you can use a voltmeter.

Find the inertia switch (usually about where the passenger's toes hit, under the carpet).

Leave its connector ON.

Using the red + meter lead, probe into the back of both wires so that the lead (or a paper clip straightened out) touches the pin. The black lead should be held onto a chassis ground or bare metal.

Turn the key to Run (the position where the dash lights come on to test them, do not crank the starter) and watch to see that 12v appears for about 3 seconds or so. It should appear each time you go from Off to Run and should appear at BOTH of the wires at that connector (assuming the inertia switch is good, not tripped).

If you get that, your fuel pump relay is working. http://www.therangerstation.com/tech_library/InertiaSwitch.html


Your model may have TWO fuel pumps, a low pressure lift /transfer pump in the tank and a high pressure pump on the driver side frame rail. you can also test for power at that high pressure pump's connector.



When you turn the key to Run, two relays click. The PCM Power relay (evidence that is working is spark is present when cranking and CEL comes on with key in Run). Once the PCM relay clicks, it routes power to activate the fuel pump relay.

See here: http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_1of3.JPG

You'll still end up paying that shop their LABOR $ to replace a warranteed fuel pump. Just the part will be covered, typically. i suggest you learn this task, using a Haynes or Chiltons Manual or advice from here. This link will help: http://www.therangerstation.com/tech_library/ford_fuel_line_disconnect.html
That job should not be hard if they replaced it a year ago, assuming it's the high pressure pump that failed.

 

[Shran]

If you do not hear the pump run, it means that your high pressure pump has failed or is not getting power. The low pressure pump in the tank is very quiet and you will not be able to hear it unless you have your ear right up next to the tank.

The troubleshooting steps above should lead you in the right direction.

 

[2tonebrown1986b2]

thank you for your reply's. Found it's a bad Fuel Pump Relay!

Thank you again!