Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
EVAP System Leak Monitor
This monitor applies to DTCs P0441, P0442, P0451, P0452, P0455 and P0456. Following conditions must be met during the test:
- Engine coolant temperature must be 113°F (45°C) or less with engine off before test drive is started.
- Atmospheric temperature is 41-113°F (5-45°C).
- Selector lever is in "D" range (A/T).
- Test may not run if fuel tank is over 2/3 full.
Monitor takes about 8 minutes to complete. To run monitor, use illustration. See Fig 1 . Perform steps as follows:
- Remove all test equipment from vehicle and install all components and connectors that were removed or disconnected during testing.
- Start engine.
- Accelerate vehicle to 55-60 MPH.
- Travel for 200 seconds or more while keeping speed at 55-60 MPH. Use 5th gear on M/T.
- While keeping accelerator pedal position constant, keep vehicle speed at 55-60 MPH for 150 seconds or more (this is when monitor runs).
- Return vehicle to shop and turn ignition off.
- Recheck for DTC(s). If any DTC(s) is set, diagnose affected DTC(s). See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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