I have had a problem for a little bit where when my fuel gauge gets a little under a quarter the truck starts to run like its running out of fuel. Once it did run out and I was able to put more fuel in and it ran great. But today when it started to chug I was right near the pumps. After a full tank of fuel and draining the fuel water separator my gauge says a quarter. Is the fuel gauge and pump one thing? Also can it be changed without lowering the tank?

Thanks

 

There was a rash of bad fuel (excess sulfur) that damaged the tank units.

Did you change the filters (both)?

Did you check fuel pressure - critical as that kills injectors.

You probably have to drop the tank... but do the above first...

Then onto wiring.

Also. Do a computer reset and see if that changes anything.




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On both my gasser and diesel, there is a noticable delay between ignition turn on and the fuel gauge registering the actual contents of the tank.

usually 10 seconds for the diesel.

 

I changed the filters right after it happened the first time about a month ago. I believe its the gauge because it only runs not so good when the fuel gauge gets below one quarter.

 

A gauge reading should have no bearing on how an engine runs, unless you are actually sucking air / crud / out of fuel.

Check fuel pressure.

 

the gauge can infact have an effect on how the truck runs. see dtc p115a. setting this code will cause the engine to go in to derate.
also running on low fuel will result in low fuel pressure and can cause pump and injector damage. nither like sucking air.

the sending unit and the pump are 2 seperate parts. the pump in on the left frame rail the sending unbit is in the tank.
to test the sending unit unplug the connector for it, its on the crossmember behind the readend.
ohm the sending unit out should be 10-180 ohms depending on how full/empty the tank is. you can also check and see if the fli pid matches the gauge reading.

 

Just for the record... its normal for the gauge to stay at what it read before you filled up for quite a while.

See the tech folder for an explanation why.

 

Thanks for the correct info, as always, cheezer

Meanwhile.. I am shaking my head at the dingo that did that software.

There are other ways to do that without setting another DTC and derating engine.


What they have done is created a lot of software headaches...


Flipping through the conditions under which the engine goes into serious limp mode for the 2011... I am just shaking my head at the number of points of failure...

 

Right now the gauge is slowly climbing back up to full as I drive. I will test the ohm's to see what it's at. If I do need to change the in tank sending unit is it easier to drop the tank of take off the bed?

 

Also one more question. Would the truck throw any DTC's if it was an electrical problem?