So far I replaced fuel pump, fuse, relay, cleaned ground wires, sending unit! is there an emergency shut off switch someplace that could be causing me trouble? or is there a module on the distributor that controls spark and fuel?
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Two of those wires are for the sending unit for the fuel gauge .The pink with black stripe is B+ to fuel pump , black is ground for fuel pump other two are for fuel sending unit . There is all so a relay in the under hood fuse box for fuel pump an fuel shut off inertia switch . Before messing with fuel pump wiring check if inertia switch is tripped , Check out this videos on fuel pump circuits . Fuel Pump Electrical Circuits Description and Operation
If you mean the inertia switch that shuts off fuel in the event of a crash, that is a Ford only part-no others have them.
Does your fuel pump turn on for 2 seconds, with key on, not start? If no, check the ECM-B fuse (20 amp) in the power distribution box by left (driver's) fender. This fuse sends power to the fuel pump relay, also in the distribution box.
To verify a bad fuel pump, check for power on the pump wire at the fuel tank connector with the engine cranking over. It is a gray wire. It should also have that 2 second signal with key on. But with engine cranking over, it should be a steady power signal. If power is on the wire, before condemning the pump, check the fuel pump ground. If ground is good, the pump will have to be replaced.
If pump is working and you have pressure up to the injectors, you will need to check the injector circuit. Post back with what you find.
Yes it is and its no fun to replace there are to many other issues with things like fuel lines tank strape the filler neck and the tank it self . These are mostly rust problems . And the pump it self has wireing issues from the harnest the wire is not a resistance wire and tends to over heat casueing a connection problem at the connecter at the pump the new pump will have upgrades that will solve this problem and some others interinaly in the pump however you will need to cut the wireing harnest to attach to new connecter to the pump its not the same and won't just plug in. What you should look at first is the fuel filter its inline under the drivers door running along the frame rail replace it . Then check the fuel relay that should be inside the glove box behind a panel thats marked relay center or relays it will be the one on the far left if you are faceing it . The other thing you could try would be the oil pressure sending unit. The way your fuel system works is it runs on a split curicut i beleive its fuse #4 that powers the relay but it also gose to the oil pressure sending unit witch goes to the fuel pump as well in case the relay goes when your on the highway you won't lose power to the fuel pump its a saftey thing dosn't make a lot of sence to me but thats how it works . If the relay is bad then it will start however it will take a long cranking time to build up enough oil pressure to trip the switch in the oil pressure sending unit to send voltage to the fuel pump. I can't candy coat this the most likely thing is the fuel pump they normaly last 10 years on this vehicle if your lucky . Good luck with it
If you didn't damage the fuel pump with the dry run, and the relays are new, and the wiring is connected properly, it should work. If you have checked all the fuses in the fuse panel and none are blown, I don't think the fuse would be anywhere else. I've got one idea you can try. It's a long shot, but I've seen it happen several times. The oil pressure sending unit or switch, is tied into the fuel pump wiring. If the oil pressure switch is bad, or the oil pressure is low, the fuel pump will be shut down. Disconnect the oil pressure switch and use a piece of wire or a sturdy paper clip and make a jumper wire. Plug the jumper into the end of the oil pressure switch wiring connector and try the ignition to see if the fuel pump works. If that doesn't work, I'll do some research on the fuse location. Good luck.
You didn't post an engine size but you are correct in thinking there is a fusible link that blew when you grounded the orange wire but there is also an inline fuse that protects the oil pressure switch and the fuel pump relay. It is usually located on the firewall.
You can check the fusible links near the starter for continuity. If one of them is burnt up start there by replacing it. If none of them are bad you will need to find the inline fuse. At least the 3.3 liter engine is set up this way.
It's in the underhood fuse box and labeled as F/ PUMP.
I personally like to backprobe the power wire to the fuel pump (large purple wire) as close to the fuel pump as possible and with the fuel pump connector plugged in. This will tell me three things.
1. If there is power than the fuses, relays, and wiring are correct. 2. If there is low voltage (less than battery voltage) there is extra resistance in the power supply wire. This could be a relay with dirty contacts or corrosion in the wiring. 3. Power is supplied to the pump for 3-5 seconds when the key is turned on. This lets me know the PCM is working correctly and receiving the crank signal from the ignition switch.
If all those check out check the ground circuit to make sure it is complete. Check for voltage on the ground wire while the pump is being powered up. If there is voltage on the ground circuit than there is resistance in the ground circuit which again could be corroded wires or corroded contacts where it meets the body.
I am pretty sure this one has a metal sending unit (the part the fuel pump mounts to. If it does and you reused the old one make sure the four wire connector that plugs into the top of the sending unit on the inside isn't burnt up. The pin that supplies power to the pump likes to burn up on these. I know it sucks that you already have it back together but if all of the above check out that is a possibility that needs to be explored. I would say that about 75% of the time the sending unit needs to be replaced because of this.
The relay will not operate untill the engine has normal oil pressure The engines oil pressure sensor has a third wire that leads to the fuel pump to prime the engine. Once the oil pressure is normal the PCM shuts that circuit off and turns on the fuel Pump RELAY
Ford had a shut off switch only. It is a saftey design Fors had for decades and no other Car maker has this option as of yet
Yours will have a fuel pump fuse, a relay to the pump. an oil sensor that is runs the fuel pump only upon starting up the engine and shuts off upon when the engine reaches normal oil pressure. When the sensor shuts off the fuel pump relay takes over until the engine is shut off. When you turn the key to the on position you will hear the fuel pump working inside the fuel tank. No need to turn the key to the start position only to the on position. If the pump is not working you have either a bad fuel pump or a oil pressure sensor. If you do hear it pumping for 5 seconds the engine should fire and die out telling you the relay or pump is bad
Fuel Pump RELAY & FUSE CHECKED & DO you Have POWER "TO" Fuel Pump ? ALSO OIL Sending Unit Supplys the GROUND To Fuel Pump , This is A Saftey FEATURE that Shuts Down Fuel If ENGINE Looses OIL PRESSURE . And If This OIL Sending Unit or also Called (OIL PRESSURE SENSOR) << If It FAILS it WILL Cause What Seems Like A Fue Pump Problem But Is Rally Just The Sensor that is BAD. HOPE this Sheds Light on Your Problem !