On my 2001 ford f350 5.4l 4x4 auto transmission regular cab truck. I had a working auto meter fuel gauge. It recently stopped after I had soldered the battery terminal cables. so I pulled it out checked the the circuit with an ohm meter and got 145 ohms the gauge read completely full I ordered a new gauge installed it it was a programmable full sweep one it also said full I have yet to yank the sender from the tank but have put additional verified grounds on the sender and the gauge with no results other than described. I am running it off the stock wiring harness and have check and rechecked everything and I am baffled that it is not working. I have trouble shot aircraft systems and Do not understand how I could have to bad gauges give the same result. I also tried the auto meter sender setting of 240-33 ohms its stuck at 1/4 tank with the tank full or 32 gallons full ( just filled ups). Any suggestions greatly appreciated.

I am going to call auto meter as Monday the 21 as I get back from my trip to the Arizona from Texas. I am glad my trip meter works.

 

You seem very confident the sending unit is working? I would not be that confident. What you could do is take the wires off the sending unit, make sure to select the correct one, and ground it, and then unground it with the key in run. When you do this back at the tank, the gauge in the dash should sweep from empty to full. If it does you know the gauge and the wiring to the front is good, and there is something wrong in the tank.

 

Here's a couple of diagrams on that system. Looks like you need to find a yellow/white wire back at the tank.

 

I only suspected the gauge because my multi-meter was reading a corresponding ohms reading to the level of the tank. but perhaps it is not good enough I am not sure. thanks for the reply and the schematics Franklin2. You bring up some good points I am just trying everything before dropping the tank. I will likely go over board on parts to make sure I never have to do it more than once.

 

I bypassed the harness by running a jumper wire from the gauge to the tank. Franklin2 your right sender is the culprit and would need to be replaced. It would seem that I would have to replace the pump assembly. I am currently looking at the Bosch 67175 for $162 or is their a cheaper way to replace individual components on these and just replace the pump with a walbro?

 

Apparently the f250-up trucks were different than the f150's around those years?

 

Other than the tank size and the lack of emission equipment is their something I am missing.

 

I did a little search and could find the sending unit for one but not the other(I forget now which). Apparently the f150's took different sending units?

 

Nice to know, Makes me wonder why, I appreciate the information thanks Franklin2.

 

Funny story So I pulled the fuel pump and noticed that I had a 2003 model pump on an 2001 truck and That the sender was working fine but the float jammed itself up by the cap. After un-jamming I just replaced the whole thing since I had another pump.

I was not to confident of cutting a hole in the bed with it over the pump and and some brace running across the bed in that location. I also have one of those plastic tanks and value my life so flying sparks on a plastic tank did not seem too good of an idea. So I did the half lift the bed method, Glad I did after running 380 miles on the tank I still had a good 6-7" of fuel in the tank( about 12 gallons) - wrestling the tank around being that full would have been a mess. Everything went fine except I rounded 2 of those torques bolts in the bed. now I need to figure out how to fix that but there is still plenty of others that are holding it together.

Looking back at my trouble shooting effort and the symptoms I Seemed to have I am not sure why I got those readings I am now wondering if I should replace my multi meter... I am also happy to say that changing the pump seemed to help the truck run better.

Thanks Again Franklin2 for helping me to the real issue.