Error Code P1445 is defined as Purge Flow Sensor Circuit High Condition.

This error code is a manufacturer-specific trouble code, meaning it does not apply to all vehicles makes. Rather, it applies only to specific vehicle makes, such as Audi, BMW, Ford, Honda, Infiniti, Lexus, Lincoln, Mazda, Mercury, Mini, Nissan, Saab, Scion, Subaru, Toyota, and Volkswagen. Specification on the definition, troubleshooting, and repairs still vary from one make and model to another.

Definition

The job of the evaporative control system is to check and make sure there are no leaks in the lines that run from the gas tank to the charcoal canister all the way to the engine. It also checks whether the gas cap is installed and sealed correctly.

When we fill our vehicle with gas, vapors in the tank are forced into a canister which is filled with activated charcoal. On hot days, the gas heats up and vaporizes, causing the vapor to push into the canister where they’re stored. The charcoal, however, can only hold a set amount of vapor. It can only hold a set amount of vapor, and at some point, it has to empty its canister. This emptying process is called the “canister purge.”

Canister purge works by powering the Purge solenoid open, which is done by the computer. This opens the vacuum line between the canister and the intake manifold. Simultaneously, this opens up the vent solenoid, which allows fresh air into the canister. As a result, the engine will suck out the gas vapors and purge the canister with fresh air. The computer also has to adapt its fuel strategy to take advantage of the other gas fumes that come from the engine.

The computer will oversee the canister and notice if it’s emptying by detecting a leaner condition (meaning all vapors have been used up), and resumes normal fuel delivery. Some vehicle manufacturers then close the vent solenoid but leave the purge solenoid open. This makes a vacuum throughout the whole fuel storage system. Once the correct vacuum level is reached, it closes the purge solenoid and waits to see if the vacuum holds. If it doesn’t, the system passes the test. If it does, then that suggests a leak.

Error Code P1445 happens when the computers see a value from the purge flow sensor that is higher than expected.

Common Symptoms

As with other error codes, this code activates the Check Engine light and registers the error code to the vehicle’s system.

Possible Causes

Here are a couple of possible causes for this error code:

  • Defective Purge Flow Sensor
  • Open or shorted Purge Flow Sensor
  • Poor electrical connection in Purge Flow Sensor circuit

How to Check

Error Code P1445 is a relatively straightforward code to diagnose, as it suggests a fault in the EVAP Purge Volume Control Valve. This valve is located on the top, rear, passenger’s side of the engine. Check the vacuum lines carefully, look for signs of cracks, holes, loose or missing connections.

Next, check the electrical connector and wire harness for broken or loose connections, look for signs of damaged wires as well.

How to Fix

Replace the purge flow sensor

Replace the purge control valve

Repair or replace purge open or shorted purge flow sensor

Repair or replace bad connection in purge flow sensor circuit

You will know if the purge control valve is bad by testing it using a multimeter (Ohms meter). Check the resistance between the following terminals:

  • Terminal (2) and terminal (1), (3)
  • Terminal (5) and terminals (4), (8)