2007 F150 Fuel Gage Diagnosis

This 2007 F150 has a fuel gage problem as it reads empty all the time. I believe the problem is a faulty sending unit but the truck has other potentially costly issues to deal with too.

[@tedthornton7791]

I have my nephew's 04 F150 4 x 4 Lariat. The original issue was speedometer and temp guage not working. Well I was physically looking for wiring issues under the truck. Found the wires and connectors you mention on the drivers side on outside of frame. Removed cover. It was encased in dried on mud. Cleaned it up. Sprayed the connections with CRC electronic cleaner. Reassembled. Now gas guage inoperable. I must have perhaps loosened a connection? Ended up replacing differential speed sensor and transmission output sensor still no change in speedometer. Rechecked and firmly verified the said connections. No change in fuel guage. Did a guauge sweep . The speedometer goes right and back left. But speedometer only twitchs. Retried sweep. Speedometer goes right fully then to 110 and stays and twitchs only when test driving.

[@PhillipBailey]

If the odometer records distance traveled over a test route but the speedo needle does not read mileage then the issue is in the cluster.

[@dreece2000]

You got some good videos pal, just trying to help anyone down the line, if anyone has 07 f150 with 5.4 make sure you use the right coil boot lengths. They are color coded. Use the wrong one and you will misfire.

[@PhillipBailey]

That is true.

[@davidjsouth231]

I wonder if the heavy rain we’ve had the last couple days has affected my connectors under the truck. 06 F150 Lariat 5.4L V8 130k miles

[@stephenr1999]

simply disconnecting or grounding the fuel level sender circuit and checking the fuel gauge operation will not work. the battery would need to be disconnected for 30 seconds, then reconnected, then the key turned on. If this is not done, the cluster will go into slosh mode and the fuel gauge will not change.

[@PhillipBailey]

Yes you are correct unless you clear the code or at least cycle the key.

[@dreece2000]

I wonder what makes them make the decision to put flex fuel on a truck. My thinking would be that since it was a king dingaling ranch then it would have had flex but that truck didnt.

[@PhillipBailey]

I think it's up to the dealer when ordering the truck. We don't have E85 available here.

[@albduke]

Seems like I can hear my fuel pump running intermittently getting noisy or something hundred thousand on it

[@PhillipBailey]

Erratic operation of the fuel pump could be worn brushes in the pump but I'd recommend to visually inspect the fuel pump driver module located by the spare tire on the driver's side frame crossmember. They corroded and fall apart. Hope this helps you

[@chris-r9u4d]

To test the gauge could a 6V or 9v small battery be connected to the wires to the gauge?

[@PhillipBailey]

No the sender in the tank is a variable resistor which creates a voltage drop.

[@lunaman98able]

New pump, new module checked wires pulled pump out twice. Chech ohms on sender. Why is my gauge stopping at 325 goes no lower? Any advice?

[@PhillipBailey]

Don't know what you're saying...fuel gage only goes to 3/4 tank?

[@gabecordova8025]

Any ideas on a store I can purchase a variable resistor box from? Thanks!

[@PhillipBailey]

Eisco Labs 6 Decade Resistance... www.amazon.ca/dp/B0725X1J25?ref=ppx_pop_mob_ap_share Just bought this one and it seems guides good quality.

[@gabecordova8025]

@@PhillipBailey thank you sir!

[@fortunatedad7695]

I have a 2012 lincoln navigator L and i have replaced the fuel pump assembly but still get erratic readings like saying low fuel when i just filled up and the cluster guage reads full but the digital display says low fuel. Have you ever encountered a ford doing this? I would appreciate any ideas on this as i jusy spent $600 on the new fuel pump. Im getting a P0462 and a B1204 Thank you

[@PhillipBailey]

Just cause the pump is new doesn't guarantee it is good. Was it changed for that problem or did the problem happen after the pump was replaced? I think your codes reflect a low resistance problem. Need to test the sender resistance to start with.

[@fortunatedad7695]

@PhillipBailey good point! yes it was changed because of these codes that came up. I traced a wire connection from what I believe comes from the top of the tank. The one in your video is under the driver's side, and mine is under the hood on the driver's side, just below the brake reservoir. I don't have wiring diagrams, unfortunately.

[@PhillipBailey]

@fortunatedad7695 for diagrams try Alldatadiy.com. it's quite reasonable imo. Once you know the wires you can measure resistance of the sender but you have to test it when the problem is present. If the gage works when the fuel level is at a specific point it suggests a bad spot on the sender but if you have the same codes and symptoms as before the pump was changed its likely not that. HTH

[@fortunatedad7695]

@PhillipBailey it's probably just a loose connection but as you know it's the matter of finding where that annoying wire lol. That link didn't work, but I'll see if my buddy can print out a diagram, thank you though. I guess I was just hoping that maybe you ran into this problem in the past and then would say oh it's just a loose connection at a so and so wire connection lol. I appreciate your time, you jusy earned a sub 😀

[@PhillipBailey]

@@fortunatedad7695 www.alldata.com/diy-us/en try this one Thar does seem to work either 🤔

[@justanothertractorguy5794]

I have a problem with my 07 ford trailer wiring, I have no power to any of the pins beside the left signal/brake, I replaced the trailer harness but still nothing. Any ideas?

[@PhillipBailey]

There should be several fuses in the underhood fuse center for the circuits. I'd start there first.

[@justanothertractorguy5794]

@@PhillipBailey thanks, found a blown 20A fuse, I’ll have to hook up to a trailer and check it

[@kevinwilks9403]

What came of this diagnostic and repair? Did the new pump get the gauge working?

[@PhillipBailey]

Yescthe new pump fixed the fuel gage and pressure leakdown

[@breckfreeride]

Wow that was an expensive fix for just the fuel level sending unit card being dirty or bad... Excellent diagnosis though.

[@PhillipBailey]

@@breckfreeride pump wasn't holding pressure after shut down either.

[@lanceschul]

Is it OK to put a little connector protector dilectric grease on that?

[@PhillipBailey]

Yes for sure.

[@lanceschul]

@@PhillipBailey Thank you. That's what I did. I just filled up and the needle sent to F immediately. Thanks for the fix. Now if I could just get the check engine light to go off. New gas cap from the dealer and it came back on. I am getting stumped on this one.

[@PhillipBailey]

@@lanceschul what code/s is it setting. I gather it's Evap related.

[@lanceschul]

@@PhillipBailey yes, P0446. I changed a couple parts out on the firewall (solenoid I think) and put a factory gas cap on. A mechanic I went to said it was the truck's computer and to put a piece of black tape over the light. Not going to do that...

[@PhillipBailey]

@@lanceschul p0446 is low voltage on the canister vent solenoid circuit. The vent solenoid is near the charcoal canister by the fuel tank. Here's some steps to check it out... 1. Check 7.5 amp fuse #5 in the Central Junction Box (CJB) (interior fuse panel) to be sure it's in place and not physically damaged. If OK, check for battery voltage from fuse #5 to the Canister Vent (CANV) solenoid at the carbon canister on the Dark Green (DG) wire with the key in the Run position. If battery voltage is not present, check for a possible connection problem at connector C3138, which is a 16 terminal connector located on the outside of the driver's frame rail below the driver's door. Repair the wire as needed and recheck operation. 2. If the DG wire shows battery voltage with the key in the Run position, check the resistance of the solenoid to verify it indicates 48-65 ohms and that the connection is making good contact to the solenoid. 3. If the solenoid resistance is OK, check for battery voltage on the Violet/White (VT/WH) wire of the solenoid with the solenoid connected. This circuit should indicate battery voltage at the solenoid and at Powertrain Control Module (PCM) pin 61 of connector 175b. If the wire shows battery voltage at one end but not the other, repair the open in the wire, again starting with checking at C3138. If the wire does not show battery voltage at either end with the solenoid connected and key on, check the wire for a short to ground and repair as needed.

[@TheNotYetProSkaters]

whats the shop labor time on this job?

[@PhillipBailey]

To change the fuel pump assembly I would likely quote that at around 2.0hrs but thats with no complications. Diagnosis of the system I'd say another hour above the R and R time. HTH

[@TheNotYetProSkaters]

@@PhillipBailey thank you bub

[@vagasduke]

what a bad spot to put that...

[@breckfreeride]

Betcha he threw a roller follower on cylinder 5

[@alexismarroquin9137]

do this wires check fuel

[@PhillipBailey]

Not sure what you're asking?

[@alexismarroquin9137]

@@PhillipBailey I have a ford 250 1995 that's not marking the gas . Can the problem be on the wiring harness

[@PhillipBailey]

@@alexismarroquin9137 it's either the sender inside the tank, the gage in the dash or wiring. Does it have dual tanks?

[@zaino660]

You need go to see a mecanic..

[@PhillipBailey]

Been doing this for 48 years. I think I'm qualified for the job...

[@puch7261]

@don Nato you need a spelling teacher lol.

[@juliangallegos7627]

Can't we all just get along? 😂

[@larrygriffin7024]

Which way did he go George?

[@dreece2000]

Why would you troll someone with half a lifetime of experience that is trying to help people out for free, the information he is giving out cost him a lot of time. Don't mess it up for everyone.