Dodge Magnum P0453: Too high Fuel Tank Pressure Sensor/Switch

The Dodge Magnum uses an evaporative emission control (EVAP), system that moves fuel vapors between the fuel tank and filler neck. They then send them to the engine for burning.  The fuel tank pressure is too high. P0453The engine light will turn on after the key is thrown.

Your Magnum will not be in danger if the sole trouble code you have is P0453.  The EVAP system controls the movement of 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.

This sensor detects if the fuel tank pressure is too high.  It measures the air pressure inside the tank and not 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:  Dodge Magnum

There are usually no symptoms that can be associated with the code.  The check engine light will illuminate (that’s why you’re here).

One thing you might notice is the smell.  If your EVAP system doesn't properly remove fuel vapor it will seek other escape routes.

There are many causes

Below are the top causes of P0453.

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

Diagnose P0453 with the Dodge Magnum

Diagnosing P0453 in your Magnum 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.

How to Make Your Home a Better Place

• If you happen to notice the sound of air escaping when you take your Magnum’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 wiring connecting to the fuel pressure sensor. If it is damaged or frayed, you should inspect it.  If it isn’t then the only way to really diagnose it is with a professional mechanic’s scanner.  This is difficult because you may need to remove the tank from your vehicle to be able to examine it.

What a Mechanical Engineer Will Do

• To determine if the sensor detects vacuum, a mechanic will take data from the fuel pressure sensor.
• You can also tell the vent valves to open or close.  You can also hear the engine running depending on your vehicle's year.

The fuel tank pressure data may be out of specification. A mechanic will check the wiring to the fuel sensor.  The fuel pressure sensor must be replaced if it is not working as expected.

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.

Dodge Magnum P0453

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 fine!