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IF you have power TO the Fuel pump relay, but not OUT of the relay for a second or two when you first turn the key ON, then your relay is most likely bad. Try swapping it with (I think your blower motor relay) You can determine the locations of the relays in your owner's manual.

I think I posted above a link on howto test a relay, if you want to do it that way.
 

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Just a thought here. Is there any type of anti theft device on the car?

The "Cranks But Wont Start" bit in this thread should probably be moved to its own thread.
Hay "Moderator" Poppy any way to do that?
 

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Just a thought here.
The "Cranks But Wont Start" bit in this thread should probably be moved to its own thread.
Hay "Moderator" Poppy any way to do that?
Yes that is do-able and a good idea. I don't want bimmerknut to get lost so when he gives acknowledgement, I'll move it, later today.
 

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Discussion Starter #25
No change today. There IS an anti-theft light just inside the windshield that blinks but it's a false sense of security. There is no system installed. I've swapped numerous relays with the FP relay. They can't all be bad. I'm not finding any broken wires yet but I'm almost sure that there is no current to that switch in the trunk. Like I said, I'm not real good with electrical trouble-shooting. I know a bad wire when it's obvious or a bad ground but that's about it. I'm going to recheck the relay socket. because the 2 wiresI checked were side by side. The blue/orange wire is lower. I think the one I got current from was Blue/Red. Looked very similar to the blue/orange and that's where I think I confused the two.
 

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Discussion Starter #27
OK fellas, here's the last of what I have. The FP relay clicks when the key is turned to ON. I have 3 HOT wires going TO the FP relay. With a meter on BOTH wires to the IFC switch in the trunk, I have momentary power as expected. The fuse #7 below the steering wheel to the PCM module is fine. I STILL hear nothing with the gas cap removed and my ear to the tube.

Logic dictates to me that unless you can think of something I'm missing, that the electric FP is shot. It's strange as my wife tells me she had ZERO issues with this car prior to overheating which caused her to park until she could afford to have it fixed. I thought perhaps the batter being disconnected for three years might have caused something electrical to be reset but other than the IFC switch in the trunk I don't know what that would be.

I'm about ready to get quotes to find out how much it would cost to have the tank dropped and the in-tank fuel pump replaced.
 

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Well if you have power to the switch in the trunk there is a good chance that pump is bad, however it would be a real kick in the butt, if the pump is good, and that you had a broken wire between the switch, and the pump, or a bad ground for the pump. Can you check for power at the pump itself?

IF you could supply power to one side of the pump, and a ground to the other, that would definitely test the pump.
 

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OK fellas, here's the last of what I have. The FP relay clicks when the key is turned to ON. I have 3 HOT wires going TO the FP relay. With a meter on BOTH wires to the IFC switch in the trunk, I have momentary power as expected. The fuse #7 below the steering wheel to the PCM module is fine. I STILL hear nothing with the gas cap removed and my ear to the tube.
I agree with Poppy. Just to make sure though, One more check, See If you can hear the fuel pump run (for the 2 sec or so) at the drivers side fuel rail, I can hear mine clearly as long as It's fairly quiet outside. I hear the relay click on then bzzzzzzzzzzzzzzzzt(fuel pump running) for 2 sec or so then the relay click off again. Also Try listening for the fuel pump in another car just as a comparison as to what you should be hearing. Also if you pull the fabric/liner off the (top shelf) in the trunk (just right of center)you should be able to see where the wires go through a rubber plug to the fuel pump. That just so you have an idea of where to look if you get under the car.
 

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Just a note..
I was looking around and found that fuel pumps cost from $110.00 to around $500.00+ I have also read that you can replace the pump without dropping the tank. ***Dont hold me to that as it's just what i have read in the past.***
 

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Discussion Starter #31
I thought the pump was IN the tank. My '78 Bimmer has one and I hear it plain as day when I turn the key on so I'm well versed in their humm. If it's IN the tank, how can I test it?
 

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See Poppy's post # 28
The fuel pump relay only powers up for a couple of seconds it should just be a short humm when you turn your ignition switch on.
Don't fall for one of the cheap pump only listed.
Your best bet is to buy a pump and sender assy if it is bad.
 

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I wonder what would happen if the fuel tank was "thwacked" with a piece of wood, during the 2 second fuel circuit power up ... If the FP was "stuck" from sitting, it might spring back into action. It might at least give you some direction.
Tow truck drivers use this trick as is necessary.
 

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Does anyone here have a wireing diagram for a 98 crown vic or merc marqui that would tell him what color(s) wire goes to the sender and to the fuel pump, and which is the ground for each?
 

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Discussion Starter #36 (Edited)
Is the attached Wiring Diagram for a '98 Grand Marquis what you need?

Excellent. Nice find! I'm no Ford Pro mechanic but I DID stay at a Holiday Inn Express last night!

Ok so the pink/blk wire we already have determined is hot and that is the power side of the FP. That leaves the ground wire as a culprit or the FP itself needs a jolt or the ground wire is defective. If I'm correct then this pretty much zero's in on the only factors remaining. Do you folks concur?

Thanks Miss!
 

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Thanks Missy!
Yes Bimmerknut, I agree, except that you checked for power at the inertia switch, and didn't confirm that you have power at the pump. There could be a break in that pink/blk wire on its way to the pump. That was the culprit that I had on my motor home. Squirrles chewed through the wiring.
 

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Discussion Starter #39
I was able to find the FP finally. It seems as though there are more than 2 wires going to it though. I did attempt to "wake it up" with a few resounding blows o a rubber mallet, but to no avail. I gave that little switch a "tap" also with the mallet and the red reset button popped up. I pushed it to reset it but that was all for naught. There is obviously no way to test the wires without removing the pump. If it becomes necessary to do that, I hope I can snake it out with out dropping the tank.

The bottom pic is of the wires going to the switch in the trunk.
ai63.photobucket.com_albums_h133_Marinersfan_Barbies_201998_20Marquis_VID00090.jpg


ai63.photobucket.com_albums_h133_Marinersfan_Barbies_201998_20Marquis_VID00089.jpg


ai63.photobucket.com_albums_h133_Marinersfan_Barbies_201998_20Marquis_VID00088.jpg
 

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I'm assuming that the bared insulation was so that you could test at the switch.
Don't you just love it when the diagram shows two wires, and you see four!?

If you do end up dropping the tank, remember that gas will weigh about 10 lbs per gallon.
 
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