Fuel level error on MC

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Just bought another 93 Mark w/105k on the clock. The fuel gauge is pegged straight up and message center gives a fuel level error message with koeo.

Car will not start. Turns over and acts like it wants to fire but no go. No pressure at schrader valve (not checked with gauge). Swapped fuel pump relay with a known working relay, no help. Going to swap VCRM next.

Battery was shot so no codes were available to pull.

Any ideas, suggestions?
 
I think you're on track for the fuel pump, but what has me puzzled is the fuel level sending unit issue. Excerpts from the manual...

Temperature and Fuel Level Gauges
The Temperature and Fuel Level Gauges are magnetic gauges. With this type of gauge, the gauge needle "balances" between two magnetic fields that are present inside the gauge. One of these fields remains at a constant strength at all times. The other field varies in strength according to current flow through the field's winding. Current flow through the winding is determined by gauge sender resistance. With low sender resistance, current flow through the coil is high; with high sender resistance, current flow through the coil is low.
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The Fuel Gauge Sender determines current flow through the Fuel Gauge winding. With a full fuel tank, sender resistance is high (about 145 ohms) and current flow is low. The needle points to"F." As the fuel level drops, Sender resistance decreases (to about 23 ohms with an empty tank) and current flow increases. The needle moves toward "E."
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Fuel Level Indicating System

The fuel level indicating system is a magnetic-type indicating system, which consists of the fuel tank sending unit and pump (9H307)located in the fuel tank, a message center with an anti-slosh feature and a fuel gauge located in the instrument cluster.

The fuel tank sending unit and pump changes resistance according to the level of fuel in the fuel tank, which varies the current flow through the message center. The message center outputs the fuel level signal to the gauge. The pointer position varies proportionately to the current flow. In this system, the fuel tank sending unit and pump resistance is low when the fuel level is low and high when the fuel level is high.

The anti-slosh feature of the message center reduces fuel gauge needle fluctuations caused by fuel movement in the tank.

The pointer of the magnetic gauge remains in relatively the same position when the ignition is turned to OFF position.
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Check IP fuse panel fuses #15 & #17.

Odd that both fuel pump and sending unit would be bad. Seems like there may be a common wiring issue or a ground fault.
 
No noise from tank, swapped VCRM, un/replug crank/cam sensor all no help. Swapping VCRM has cleared fuel level error, but gauge still does not read correct. Going to pull the tank and swap with one from my parts car, I know it works since I drove it home and have moved it around the drive before. Plus it's already out of the car!

Was looking through paper work in glove box and car was last tagged in 01. I took off fuel filter and can smell the lacquer in the old gas. If/when I get it running I will Seafoam the fuel tank/lines/injectors.

Also pulled all fuses in cabin and under hood. Only bad one was cigar lighter.

Thanks guys for your help. I'll post results later.
 
Its alive. THe 8 year old, full tank of gas was the culprit. After installing parts tank I turned on igniton and orange gas squirted out where filter was removed. After about 15 mins of key on/off the lines started to clear out. Put new filter on and car started right up. Idled rough for about 5 mins but smoothed out and run great.

Not bad for a $700 car.
 
Go Fast Get Tickets said:
Its alive. THe 8 year old, full tank of gas was the culprit. After installing parts tank I turned on igniton and orange gas squirted out where filter was removed. After about 15 mins of key on/off the lines started to clear out. Put new filter on and car started right up. Idled rough for about 5 mins but smoothed out and run great.

Not bad for a $700 car.
Click to expand...

No fair withholding information! :p If you'd said the gas was 8 years old, we'd know what the problem was! LOL :D

Glad you got it running. Hopefully it will work out for you. ;)
 
I assumed that it was driven until 08 when owner died. That's what I get for assuming!

Its a full tank of varnish. Anybody doing wood work is welcome to it. It's a pretty orange. :D
 
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