Help... Fuel Gauge Diagnosis

[Robert K]

Hello...

I recently purchased a 2001 Ford Expedition EB. Unfortunately, the person that I purchased it from was not honest about an issue regarding the fuel gauge and some other items (unrelated to this problem). Luckily, I didn't find out the hard way by running out of fuel on the highway. My fuel gauge is stuck on about 3/4 and does not move.

Through researching the forum, this is what I have done...

I have entered the instrument cluster self-diagnosis mode (pressing the trip/reset button while key into the on position). When I perform the gauge sweep, all gauges move except for the fuel gauge. My initial assumption is that the fuel gauge has failed on the instrument cluster and I should replace it.

When pressing through the various diagnostic sequences, I eventually come to FUEL, which shows 029-030. I recently filled up the tank - is that actually the fuel in the tank since it is a 30 gallon tank? Wondering if that is being sent by the sender unit?

Also, my display on the ceiling is consistently displaying "0 miles to empty". That has me concerned that the sending unit might not be transmitting properly, perhaps I have a simultaneous problem with the instrument cluster and the sending unit?

If I can determine that the computer is actually getting the right data, I could just add an external OBD display that shows the fuel level, as well as some of the other real time diagnostics & gauges. However, it would be nice to just fix the problem and not have to worry about it.

I need some advice on where to look. Is the ceiling display tied to the instrument cluster or does it receive data directly from the ceiling unit? Is the FUEL display during the diagnostic mode actually gallons in the tank?

Thank you for any advice...

 

[Bedrck47]

Welcome to the Forum

How many miles on the expy?

I don't have the time at present to offer you some suggestions But I will get back to you later today.

Had a similar problem on my 01 was the fuel sender that was faulty although the pump was OK
I replaced the whole assembly.

Can you read and understand wiring diagrams

 

[Robert K]

Mileage is 159K, and I do have the odometer coming and going problem, my understanding is a poor solder joint that is very common. I'm not really concerned about that issue.

For the most part, I can read and understand wiring diagrams.

 

[Robert K]

Not sure if what I was reading during the diagnostics of FUEL being around 029-030 as being gallons remaining. I hooked up my OBD2 reader and none of software seems to pick that up as fuel remaining. I guess I'll find out after I burn some gas in the tank.

 

[Bedrck47]

Under the air filter you will see TWO connectors C148 and C149 Print 151-02 will show the location You need to disconnect C148 You can disconnect both if you want to After you disconnect C148 Put the key in the ignition and just turn it to the run position NO NEED TO START THE ENGINE see what the fuel gauge reads.

 

[Bedrck47]

The odometer problem is a common issue on the first Gen. expeditions Its an easy fix and there are some good videos on youtube on the procedure. Takea about an hour or less to make the repair

 

[Bedrck47]

With the amount of miles on the Expy and depending on the results of you disconnecting C148 it may be best to replace the fuel pump assembly

 

[Robert K]

Thanks... I'll disconnect C148 when I get home this evening to see if there is any change in the gauge.

 

[Bedrck47]

Remove the air filter The housing then just pulls up. May take a little force to pull up

 

[Robert K]

What should I expect to see happen with the fuel gauge after I disconnect? During the gauge sweep test, the thing didn't budge at all. When the car is off, it still shows at 3/4.

 

[Bedrck47]

I hope that the gauge will show empty

 

[Robert K]

Unfortunately, no change in the fuel gauge after disconnecting the both connections.

 

[stamp11127]

See if this applies to your model:

https://www.ford-trucks.com/forums/141841-odometer-test-codes.html

 

[Robert K]

It may apply to my model, looks like the reading on the FUEL is the analog to digital conversion, not fuel level. I'm starting to feel as if I have an instrument cluster failure as well as a sending unit failure. I could easily deal with the instrument cluster failure, but the thought of dropping the fuel tank seems like more of a hassle than what I want to deal with. I guess I could monitor the fuel level by keeping an average MPG log and use my odometer as the trigger point for refueling.

 

[stamp11127]

You can take the cluster out and fix the odometer and check the traces to the gauge.
If you replace the cluster then new one needs to be married to the pcm or you're not going anywhere.

 

[Robert K]

Pencil, paper and simple math might be lesser of a headache... starting to hate the computer stuff in the cars these days.

 

[Bedrck47]

Dropping the fuel tank isn't all the bad of a job ass long as the tank is near empty

Look back to the wiring diagram and look at the fuel sender Follow the wire from the sender to C148 and if you have a ohm meter read the resistance between those two wires

You should get something between 15 ohms (empty) to 160 ohms (full)

Sending you a PM check the inbox

 

[Bedrck47]

Go back and look at print 25-07 If you look at where the sending unit connects to the Inst Cluster from C148 you will see circuit 29 With C148 disconnected ground that wire that goes from the male side of C148 Make a jumper wire and connect circuit 29 to the NEG battery terminal then turn the key to run DO NOT START This should cause the fuel gauge to read empty If the gauge still doesn't move then time to repair or replace the INST cluster

 

[John Stover]

My 01s gauge will work accurately once in a while but mostly stays at exactly one-half of a tank. When the ignition is off, the gauge zeros out. I have been relying on the trip odo, but would like to correct this problem with the gauge. Anyone's suggestions would be welcome. For the record, all other functions on the cluster work normally

 

[Robert K]

Hey John, sounds like your fuel sending unit may be periodically sticking in the tank. In my research, people have said that a good fuel cleaner may take care of the problem, otherwise you'll have to replace the unit.

Unfortunately, my situation just got a little worse. As I said in my original post, the seller lied about many things - he also failed to mention that he replaced the dash board to show lower mileage and may have disconnected the check engine light. When I tried to get it inspected, I have four sensors not available. In an attempt to obtain a waiver, the history of inspection showed that my Expedition actually had 337K miles at last inspection, rather than the 159K that was showing on the odometer when I purchased it.