EVAP Leak Monitor Pinched Hose Found

Name of Code:
EVAP Leak Monitor Pinched Hose Found

When Monitored:
Immediately after a cold start, with ambient temperature between 40° and 90°F and coolant temperature within 10°F of ambient temperature. If the PCM suspects a pinched hose it will not set a fault until it runs the EVAP purge flow monitor. If the purge monitor does not pass then the pinched hose fault will be set. Purge flow is monitored with engine temperature greater than 170°F, engine in closed loop, engine idling for 2 minutes, no low fuel, MAP less than 15.7 inches mercury, and barometric altitude less than 8,000 feet.

Set Condition:
Leak Detector Pump (LDP) must pass stricter EVAP system test first. No air flow through the evaporative system is detected by the EVAP monitor.

Theory of Operation:
After passing the leak detection phase of the test, system pressure is maintained until the purge system is actuated, in effect creating a leak. If the cycle rate increases due to flow of the purge system, the test is passed and the diagnostic test is complete. If not, there is an obstruction in the system. The purpose of the evaporative system is to recycle the accumulated fuel vapor found in the fuel tank. The fuel vapor is temporarily held in the EVAP canister and is recirculated via the EVAP solenoid through the air intake system and consumed during combustion. The evaporative system consists of the fuel tank, vapor flow control orifice, EVAP solenoid, and EVAP canister connected by a series of hoses and connectors.

Possible Causes:
- Rubber hose(s) kinked from solenoid to throttle body
- Hose plugged from solenoid to canister
- Hose plugged from throttle body to solenoid
- Hose plugged from tank to canister