Chevrolet Malibu P0453: Too high fuel tank pressure sensor/switch

Chevrolet Malibu employs an evaporative emission control system (EVAP) to transfer fuel vapors to and from the fuel filler neck. They are then sent to the engine for burning.  If the fuel tank pressure is too high P0453The engine light will turn on after the key is thrown.

The Malibu won't fail to function if P0453 is the sole trouble code.  The EVAP system controls the movement of fuel vapor.  It doesn't matter if it does that, or not. This has no impact on how your engine works.  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.  It measures the air pressure inside the tank and not the 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:  Chevy Malibu

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

You may only notice the fuel smell.  If your EVAP system doesn't properly remove fuel vapor it will seek other escape routes.

The causes

Below are the top causes of P0453.

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

Diagnose P0453 with the Chevy Malibu

Diagnosing P0453 in your Malibu 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 Malibu’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.
• The vent valve will be opened and closed by them.  This can be heard depending on which year and model of the vehicle.

A mechanic can inspect the wiring leading to the fuel pressure sensor if the fuel tank pressure is not within the specifications.  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.

Chevy Malibu: 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.  It's possible to fix your Malibu.