Evaporative Emission System Leak Detected Small Leak
Table of contents
P0442 MINI Possible Causes
- Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in the fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking
How do I fix code P0442 MINI?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
- The P0442 code means that the control module has detected a small leak in the Evaporative Emission (EVAP). Loose fuel tank filler cap is the most common cause that triggers the P0442 code.
Cost of diagnosing the P0442 MINI code
The cost of diagnosing the P0442 MINI code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Possible a noticeable fuel odor caused by the release of fuel vapors
P0442 MINI Description
The evaporative system monitoring permits the detection of leaks in the evaporative system with a diameter of 0.02 inches and up. By means of a Diagnostic Module Tank Leakage (DMTL), an electrically actuated pump located at the atmospheric connection of the evaporative canister, a pressure test of the evaporative system is performed.
During the Reference Leak Measurement, the electrically actuated pump delivers through the reference restriction. The engine-management system measures the pump’s electrical current consumption in this section.
During the Leak Measurement, the electrically actuated pump delivers through the charcoal canister into the fuel-tank system. The pressure in the evaporative system may be up to 2.5 kPa depending on the fuel level in the tank. The engine-management system measures the pump’s electrical current consumption. A comparison of the currents of the reference leak measurement and the leak measurement is an indication of the leakage in the tank.