I need help! I have a 99 F250 and the fuel gauge doesn't read very accurate. I was driving down the road to take my kids to school and the gauge reads 1/4. Well I get to the next light and it dies, no fuel. The low fuel light never came on and the gauge still read 1/4. So long story short, me and the kids walk 1 1/2 miles, because I forgot my cell phone, with a fuel gauge that read 1/4 tank. Is there any way to fix this? A new sending unit? There has to be something to correct this.

Rusty

 

Sometimes the float can get stuck. You might just have to drop the tank and check it out.

good luck,
Steven

 

You might want to check with a Ford dealer. I think they have diagnostic equipment that can check both the dash gauge and tank unit for accuracy.

 

Just picked up my truck from the dealer this past Friday evening. Same problem. SSB (no, not a TSB) suggest SULPHER DEPOSIT build-up on the tank sensor. Added CHEVRON TECHRON to desolve sulpher deposits. Added 10 gals fuel and drove about 150 miles so far. Seems to be correcting itself. Ask ANY mechanic about CHEVRON TECHRON. Great stuff. Just didn't know it was used in diesels too.

 

The Ford test uses 2 resisters to test the gauge. This test will determine if it's the sender or something else. Test involves unplugging the sender at the tank. On the plug going to the computer and gauge, put a 15 ohm resister in place of the sending unit. Gauge should read empty. Put a 160 ohm resister and the gauge should read full. After putting the resisters in, turn the key on to read the gauge.

Only 2 wires on the plug. To get the 160 ohms, resister values are added when in series. Just keep added to get the 160. You could test along the way as well. 90 ohms or so should be 1/2 a tank.

My gauge has been driving me nuts. I finally found that on the ground wire in the plug, I had 3.5 ohms. After I cleaned the ground connection at the air filter. Ground now reads 0 ohms and the gauge seems to be working much better.

Just some ideas for you. Hope this helps. Mark