Ford F150: Too high Fuel Tank Pressure Sensor/Switch

Ford F150 employs an engine-burning evaporative control (EVAP) to transfer fuel vapors to and from the tank and neck.  The fuel tank pressure is too high. P0453The engine light will turn on after the key is thrown.

Your F150 will not fail if the trouble code is P0453.  It is responsible for transferring fuel vapor.  It does not matter whether it's doing this or not. The engine will still run as normal.  This code is not to be ignored.

The EVAP system does not work all the time.  It uses a  valve to open and close the system to release fuel vapor into the engine to be burned off.

It is the fuel tank pressure sensor that detects excessive pressure.  This sensor measures air pressure within the tank. It does not measure fuel pressure.  When it does, the P0453 signal is sent.  The fuel tank pressure sensor can be found on top of the fuel tank, fuel pump or fuel level sending device.

The opposite of this code is P0452, which is thrown whenever the system pressure is too low.

P0453 Symptoms:  Ford F150

This code is usually not associated with any symptoms.  The check engine light will illuminate (that’s why you’re here).

One thing you might notice is the smell.  If the EVAP isn't working properly to remove the fuel vapor from the air, the system will look for other routes.

There are many causes

Below are some more frequent causes of P0453.

• Charcoal canister Clogged vent valve
• Fuel tank pressure sensor damaged (sensor or wiring).
• Fuel tank damaged
• PCM/ECM (highly unlikely)

Diagnose P0453 with the Ford F150

Diagnosing P0453 in your F150 can be challenging if you don’t have a scan tool that is capable of reading the fuel pressure sensor data or capable of commanding the vent valve to open and close.

Here are some things you can do at home

• If you happen to notice the sound of air escaping when you take your F150’s gas cap off, that is a telltale sign that the vent valve is bad, or the charcoal canister is bad(it’s pressure leaving the gas tank).  Once you have driven for some time, turn off the gas cap and go somewhere else.  It’s hard to notice the sound when you’re at a noisy gas station.
• Examine the fuel tank pressure sensor wiring and determine if any damage or fraying is evident.  If it isn’t then the only way to really diagnose it is with a professional mechanic’s scanner.  It can be difficult to look at the tank without dropping it.

What a Mechanical Engineer Will Do

• To determine if the sensor detects vacuum, a mechanic will take data from the fuel pressure sensor.
• The vent valve will be opened and closed by them.  This can be heard depending on which year and model of the vehicle.

The fuel pressure sensor wiring will need to be checked if it isn't in spec.  A mechanic will inspect the wiring leading to the fuel pressure sensor and replace it if that is found.

If the vent valve is on and the pressure sensors are fine, the charcoal canister needs to be replaced.  If the vent valve doesn’t come on, it will need replacement in order to clear P0453.

If it looks good, the PCM could have a problem.

Ford F150 P0453 Conclusion

That’s pretty much it.  While there are only a couple of common things that’ll cause P0453, there it can be tough to diagnose it without the right equipment.  It’s not going to leave you stranded on the side of the road either.  You're going to be able to fix your F150.