Ok so I've had a p0442 for quite a while now on my 2010 2.3l ranger. Its a small evap leak. I've replaced the purge canister valve and the solenoid vent valve and the gas cap. I've been seeing that it could be the fuel tank pressure sensor? Where might that be located? Any thoughts on this? This started after I had the fuel pump replaced

 

For those that don't have the OBD Codes memorized
P0442 Evaporative Emission Control System Leak Detected (small leak)

This would be as described, a small leak so not
P0455 Evaporative Emission Control System Leak Detected (gross/big leak)
Or computer would have used P0455

If it started after fuel pump was replaced then I would suspect gasket seal for the ring on the assembly or crack in filler tube since it had to be unhooked and moved around to access pump assembly

The pressure sensor is on the top of fuel pump assembly but its not your problem

These computers are not very "smart" but they are logical, they set codes for specific reasons, they don't guess, or "think"
They have literally hundreds of codes to use
Here are a few for this pressure sensor:
P0450 Evaporative Emission Control System Pressure Sensor Malfunction
P0451 Evaporative Emission Control System Pressure Sensor Range/Performance
P0452 Evaporative Emission Control System Pressure Sensor Low Input
P0453 Evaporative Emission Control System Pressure Sensor High Input
P0454 Evaporative Emission Control System Pressure Sensor Intermittent

It didn't use these because there is no issue with pressure sensor, there is a "small leak" detected by pressure sensor, so computer used P0442

Always look up OBD codes on a FULL LIST, like this one: https://therangerstation.com/tech_li...II_codes.shtml

Look at the codes the computer did NOT use to eliminate what isn't the problem, that will help you find what is the problem

 

Think I found the problem. Slid the bed back and found this unplugged

 

Good work

 

P0442 My mechanic solved it by disassembling the gas tank, he changed a viton seal that is submerged in the tank. I ordered this seal to be prepared according to the model.

assembled part

damaged viton seal

inside view of the tank

 

Odd failure but good info, thanks