Filled up with Shell 93 and 1 bottle of Lucas. Almost immediately Ultragauge gave me a code P0462. Truck runs normal and no service engine soon light is on. Any thoughts?

 

fuel level sensor circuit low input.

 

I get that code every now and again as well, It is as Mike said.

 

Put in a new fuel pump assy with the gas gauge unit built in.
Probably will fix it.

Or keep the tank full and then the gas does not slosh around and make the
old wire wound variable resistor loose connectivity with the sliding mechanical part.

You can probably make this happen by going to 1/2 tank.
Then go 3 mph, brakes, 3 mph, brakes, 3 mph brakes.
That sloshes the gas around.

 

The funny thing is that the truck didn't start doing it until it was full. When I first got the truck last month I filled it up, then I drove it a little. Added $20 the other night, no problem. Now I fill it up and I have a problem. I guess I better start doing some parts shopping.

 

Is this telling me the sensor is going bad or the fuel pump is going bad? The gauge is still functioning fine.

 

Attached is the more involved explanation of the code from the Bosch ECU manual. Basically, the signal from the gauge sender went "low", less than a very small voltage, and this code is recorded. It does not turn on the check engine light (MIL). It is there to help technicians see what was going on with other stored codes, like misfires. It may have been caused by a "bad spot" on the sender, like a bad spot on a volume control where the sound gets scratchy. Reset and ride. If it keeps doing it try to keep fuel at higher level (like fill up when 1/2 tank). The pump is not causing the signal. But the sensor is part of the pump assembly. The gauge appears normal because of the anti-slosh circuitry that smooths out variations caused by gas movement around on turns, stops, etc. If it was not "smoothed" the gauge signal would be wiggling all over the place while vehicle in motion.

 

Thanks for the explanation. I reset the Ultragauge several times and the code comes back. I will try disconnecting the battery and seeing if that helps.

 

If code comes back, the system is generating it. You can try reading the particular wires with a meter. Pink with black and green with black at the tank or cluster or some spots inbetween.

 

I am completely lost when it comes to trying to read a multimeter. I disconnected and reconnected the battery. That seems to have fixed the problem for now. I'll know more tomorrow. I'm planning to take the truck on a Houston Land Rover Club GTG. Should be about a 3 hour round trip.