What is this thing, and why does it only have one wire connecting to it!?

[Noflers]

The radiator connects to this hub or whatever it is. The only check engine code on the truck points to the fuel tank pressure sensor (which has been replaced but stills sends a code...)

 

[RonD]

1 wire means it is a "sender" not a sensor, it uses the engine as the Ground, so it is for a dash board gauge, not computer.
From it's location it would be the temp sender, other sender is the oil pressure sender, and I believe oil level is also uses a sender if so equipped.

What engine is it?

ECT(engine coolant temp) Sensor has 2 wires and is usually located near the temp sender, as they need the same information......coolant temp, this one is only used by the computer.


EVAP(fuel tank pressure) codes can take a long time to clear, keep fuel level in tank between 1/4 and 3/4, so don't drive to empty and don't full up, for a few weeks, PITA but it helps.

 

[Noflers]

It's the 3.0, auto, XLT.

The code says the voltage is high on the FTPS. I replaced it, while I was doing that I found a severed wire so mended that also.

 

[RonD]

With engine off and key on use a Scan tool to look at the Fuel Tank Pressure Sensor(FTPS) voltage, should be listed as FTP V in the menu
It should be near 2.5volts, 2.3-2.8v is spec.
If it is then code will clear on it's own

If it is 4.5v or higher then remove gas cap and see if voltage changes, if so then EVAP purge or tank vent is blocked.

If voltage stays high then wire to FTPS is probable shorted, PITA to trace it, but trace it you must, having someone watch the voltage while you jiggle the wires can help

 

[BCanuck]

One way to find out what it is, unplug it and check your gauges. (Then plug it back in of course)