DTC P0453 Diagnostic Information (SUSTIPS 1111-04)

Publication date: 2012-01-01
Reference number: SUSTIPS 1111-04

DTC P0453 DIAGNOSTIC INFORMATION

TECHNICAL INFORMATION TIP - MANUFACTURER

Reference Number(s): SUSTIPS 1111-04, Date of Issue: January 01, 2012

SUBARU:

All Models

SERVICE INFORMATION

If you receive a customer concern of a Check Engine Light on and find a DTC P0453 stored in the ECM memory, the fuel tank pressure sensor may not be the source of the condition. The description for P0453 reads: "EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE SENSOR HIGH INPUT". When the ECM grounds the Fuel Tank Pressure Control Solenoid Valve, it "assumes" the valve is operating normally. With the solenoid valve opened, fuel tank vapor pressure is released into the charcoal canister. When the resulting pressure change the ECM is looking for after it opens the valve does not occur, the code sets for what the ECM believes is a failed Fuel Tank Pressure Sensor (P0453). The root cause of the problem is more likely to be a stuck CLOSED Fuel Tank Pressure Control Solenoid Valve. An easy check to confirm pressure sensor operation is to remove the fuel cap while monitoring fuel tank pressure with your SSMIII. Tank pressure will be released to the atmosphere and the reading should drop to zero.