fuel system fuses?
- Thread starter pyle
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PalmettoMarkVIII
Registered
RE: fuel system fuses?
To check the fuel pump manually, go by Frankie X's instructions in the link below. His response is about six or seven responses down. He is explaining how to manually turn the pump on to purge a gas tank with contaiminated fuel. The fuel pump relay is in the same spot on my '94, as the '97 mentioned there, so gen1 and gen2 are apperantly the same.
http://www.lincolnsclub.org/forum/d...opic_id=9917&mesg_id=9917&listing_type=search
Edit:
Try changing your fuel filter, also, could be clogged; much cheaper than the pump.
The relays are the same, I believe, try swapping with the adjacent one to check the relay. With the row of relays as the "top" row, the fuel pump relay is the last one on the right.
To check the fuel pump manually, go by Frankie X's instructions in the link below. His response is about six or seven responses down. He is explaining how to manually turn the pump on to purge a gas tank with contaiminated fuel. The fuel pump relay is in the same spot on my '94, as the '97 mentioned there, so gen1 and gen2 are apperantly the same.
http://www.lincolnsclub.org/forum/d...opic_id=9917&mesg_id=9917&listing_type=search
Edit:
Try changing your fuel filter, also, could be clogged; much cheaper than the pump.
The relays are the same, I believe, try swapping with the adjacent one to check the relay. With the row of relays as the "top" row, the fuel pump relay is the last one on the right.
PalmettoMarkVIII
Registered
RE: fuel system fuses?
Reviewing my '94 service manual, the fuel pump has TWO circuits controling it. The afore mentioned relay and the VCRM. The f.p. relay initially pressurises the fuel line; after a second or so, it quits. This happens if you turn ignition to RUN, but do NOT start. If you turn to START, the VCRM(Vehicle Control Relay Module) takes over and supplies power until the engine quits, then cuts power. I'm not sure which circuit is considered "secondary", but the f.p. relay is easy, just swap an adjacent relay (or get a new one), also check for power on the power side pin of the relay. As for the VCRM, it has a fuse; after the top row of relays, it is the first fuse on the left on the next row (first row of fuses, after relays). If fuse is good, check power to fuse, if good, check connector to VCRM, if connection is good, then probaly bad VCRM. The VCRM is in front of the radiator, behind the grill.
Reviewing my '94 service manual, the fuel pump has TWO circuits controling it. The afore mentioned relay and the VCRM. The f.p. relay initially pressurises the fuel line; after a second or so, it quits. This happens if you turn ignition to RUN, but do NOT start. If you turn to START, the VCRM(Vehicle Control Relay Module) takes over and supplies power until the engine quits, then cuts power. I'm not sure which circuit is considered "secondary", but the f.p. relay is easy, just swap an adjacent relay (or get a new one), also check for power on the power side pin of the relay. As for the VCRM, it has a fuse; after the top row of relays, it is the first fuse on the left on the next row (first row of fuses, after relays). If fuse is good, check power to fuse, if good, check connector to VCRM, if connection is good, then probaly bad VCRM. The VCRM is in front of the radiator, behind the grill.
RE: fuel system fuses?
located vcrm ,it seems to be making clicking noises when I take out fuse and replace it.How do I test it? switched relays around it didnt help ,tried to run fuel pump direct with jump wires in relay no luck I think I touched the right pin , it had power coming into it. Still trying any ideas
located vcrm ,it seems to be making clicking noises when I take out fuse and replace it.How do I test it? switched relays around it didnt help ,tried to run fuel pump direct with jump wires in relay no luck I think I touched the right pin , it had power coming into it. Still trying any ideas
PalmettoMarkVIII
Registered
RE: fuel system fuses?
Diagnosis & testing is refered to the Powertrain control\Emissions Diagnosis Manual, which I don't have. Only thing I can suggest now is to swap the VCRM for another.
EDIT & addition to previous response:
While the VCRM is a second relay involved, per service manual, I confused it in my response before. A different module controls start and power\no power to fuel pump. The PCM(Powertrain Control Module)controls the f.p. relay during start and engine running. It cuts power when rpm of engine drops below 120. The VCRM is mentioned as one of two power supply relays to fuel pump, but that is all that is mentioned of it.
!!!!There is another fuse to check!! A combo PCM\VCRM fuse. It is on bottom row, fifth from left. First slot on left, bottom row, is a ABS Diode, then four fuses to the PCM\VCRM fuse.
The PCM\fuel pump relay supplies power through the inertia fuel cutoff switch. Be sure and try the reset button in the trunk also.
BTW: The PCM is under the dash near steering column.
Further Edit:
I checked the pinout on the VCRM Connector in EVT manual. Three pins (of 24)involve fuel pump.
Pin 10 - BR/W (Wire Color) High Speed Fuel Pump Relay Output
(starting & high fuel demand)
Pin 18 - LB/O (Wire Color) Fuel Pump Input
Pin 24 - PK/BK (Wire Color) Power to Fuel Pump (Low Speed)
Pins are laid out as such:
13-18 space 19-24
1 - 6 space 7 -12
Diagnosis & testing is refered to the Powertrain control\Emissions Diagnosis Manual, which I don't have. Only thing I can suggest now is to swap the VCRM for another.
EDIT & addition to previous response:
While the VCRM is a second relay involved, per service manual, I confused it in my response before. A different module controls start and power\no power to fuel pump. The PCM(Powertrain Control Module)controls the f.p. relay during start and engine running. It cuts power when rpm of engine drops below 120. The VCRM is mentioned as one of two power supply relays to fuel pump, but that is all that is mentioned of it.
!!!!There is another fuse to check!! A combo PCM\VCRM fuse. It is on bottom row, fifth from left. First slot on left, bottom row, is a ABS Diode, then four fuses to the PCM\VCRM fuse.
The PCM\fuel pump relay supplies power through the inertia fuel cutoff switch. Be sure and try the reset button in the trunk also.
BTW: The PCM is under the dash near steering column.
Further Edit:
I checked the pinout on the VCRM Connector in EVT manual. Three pins (of 24)involve fuel pump.
Pin 10 - BR/W (Wire Color) High Speed Fuel Pump Relay Output
(starting & high fuel demand)
Pin 18 - LB/O (Wire Color) Fuel Pump Input
Pin 24 - PK/BK (Wire Color) Power to Fuel Pump (Low Speed)
Pins are laid out as such:
13-18 space 19-24
1 - 6 space 7 -12
Frankie X
Registered
RE: fuel system fuses?
Pyle, you don't need to probe the PCM control pins or bother with the VCRM. The code 542 tells you that.
A quick lesson: Any high load relay controlled circuit has been divided into two portions by the engineers who developed PCM diagnostic software.
PRIMARY = CONTROL. In the case of your fuel pump circuits, this means all circuits from the PCM and the VRCM that will control the low current winding in that fuel pump relay in the fuse box.
SECONDARY = LOAD. The secondary circuits are the power feed into the contact side of the fuel pump relay, its internal contacts, and the power feed out to the pump itself.
Your diagnostics are pretty simple: With the ignition on, you will have two powers in the relay socket of the fuse box.
One will be there at all times. This comes from the fuel pump fuse and is load power.
The other is fed from the PCM. Ford calls it "Key Power", but that's not really true. When you turn your key on, the PCM relay is energized, turning the PCM on. The PCM, in turn, provides both power and ground to the fuel pump relay. If, after one full second, the PCM does not see engine RPM, it kills the ground signal to the fuel pump relay, turning it off. THE POWER REMAINS AS LONG AS THE PCM RELAY IS ENERGIZED.
If you have both powers and the relay clicks when you cycle the key, your choices are limited to the fuel pump itself or a poor connection to the pump.
My money is on the pump.
Ford pumps come complete with flange,gasket, and sending unit,but are expensive. You may want to check aftermarket.
Any UAP outlet can get them.
Canadian Tire sells a stock equivalent pump made by Carter that I know poeple have been happy with.
If you're planning on modifications in the future, you may want a high-flow pump. You have one of the best Modular Ford performance shops in Canada just north of you in Woodstock. Check out www.seanhylandmotorsport.com .
When I bought my Mark, the other techs in my shop all laughed and told me,
"Every day in which I get up, go outside to find my Mark still sitting level, and make it to work without the fuel pump or alternator crapping out, I must say, 'Thank you Lord for this good day!'"
Pyle, you don't need to probe the PCM control pins or bother with the VCRM. The code 542 tells you that.
A quick lesson: Any high load relay controlled circuit has been divided into two portions by the engineers who developed PCM diagnostic software.
PRIMARY = CONTROL. In the case of your fuel pump circuits, this means all circuits from the PCM and the VRCM that will control the low current winding in that fuel pump relay in the fuse box.
SECONDARY = LOAD. The secondary circuits are the power feed into the contact side of the fuel pump relay, its internal contacts, and the power feed out to the pump itself.
Your diagnostics are pretty simple: With the ignition on, you will have two powers in the relay socket of the fuse box.
One will be there at all times. This comes from the fuel pump fuse and is load power.
The other is fed from the PCM. Ford calls it "Key Power", but that's not really true. When you turn your key on, the PCM relay is energized, turning the PCM on. The PCM, in turn, provides both power and ground to the fuel pump relay. If, after one full second, the PCM does not see engine RPM, it kills the ground signal to the fuel pump relay, turning it off. THE POWER REMAINS AS LONG AS THE PCM RELAY IS ENERGIZED.
If you have both powers and the relay clicks when you cycle the key, your choices are limited to the fuel pump itself or a poor connection to the pump.
My money is on the pump.
Ford pumps come complete with flange,gasket, and sending unit,but are expensive. You may want to check aftermarket.
Any UAP outlet can get them.
Canadian Tire sells a stock equivalent pump made by Carter that I know poeple have been happy with.
If you're planning on modifications in the future, you may want a high-flow pump. You have one of the best Modular Ford performance shops in Canada just north of you in Woodstock. Check out www.seanhylandmotorsport.com .
When I bought my Mark, the other techs in my shop all laughed and told me,
"Every day in which I get up, go outside to find my Mark still sitting level, and make it to work without the fuel pump or alternator crapping out, I must say, 'Thank you Lord for this good day!'"
RE: fuel system fuses?
Thanks for the info on my problem everyone I would have no idea what to do with out this web site. I am about to attempt to drop the tank on it.I didnt relize the exhaust pipe is in the way does it have to be removed can I drop the tank far enough with out taking it off? I believe the fuel pump is done ,there are 270 kms on the orginal pump .
Thanks for the info on my problem everyone I would have no idea what to do with out this web site. I am about to attempt to drop the tank on it.I didnt relize the exhaust pipe is in the way does it have to be removed can I drop the tank far enough with out taking it off? I believe the fuel pump is done ,there are 270 kms on the orginal pump .
Frankie X
Registered
RE: fuel system fuses?
Drop the exhaust.
I've seen guys leave it up, then partially drop the tank, leaving it hung up over the pipes and groping around above the fuel tank with only the right side lowered. It wasn't pretty.
If this is your first time, drop the tank down properly so you will have lots of room to work and see.
If you decide to go aftermarket for your pump, be sure to get a new pump flange O-ring (gasket) and lock ring. Never, never, never try to re-use the old pump o-ring. I guarantee it will leak when the tank is full!
You may have to go to the Dealer for the rings.
Drop the exhaust.
I've seen guys leave it up, then partially drop the tank, leaving it hung up over the pipes and groping around above the fuel tank with only the right side lowered. It wasn't pretty.
If this is your first time, drop the tank down properly so you will have lots of room to work and see.
If you decide to go aftermarket for your pump, be sure to get a new pump flange O-ring (gasket) and lock ring. Never, never, never try to re-use the old pump o-ring. I guarantee it will leak when the tank is full!
You may have to go to the Dealer for the rings.