P1486 EVAP Leak Monitor Pinched Hose Found

SAFETY PRECAUTIONS

WARNING
Take the following precautions to prevent personal injury while using this test equipment.

Keep lighted cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases Keep the test area well-ventilated.

This equipment is designed to be used or the vehicle evaporative system only. Using the equipment in a manner for which it was not designed could be dangerous procedure.

The vehicle fuel tank must be between 3 gallons and 17 gallons of gas when connecting this test procedure. Pressurizing a tank containing less than three gallons of gas could result in the ignition of fumes, causing an explosion.

Wear protective eye wear that meets the requirements of OSHA and ANSI Z87.1-1968.

When using the battery as a power source, connect the RED (+) battery clip to the positive vehicle battery terminal, and connect the BLACK (-) battery clip to a good ground away from the battery.

If the vehicle being tested in not on a hoist, set the parking brake and block the wheels before starting the test.

NAME OF CODE
EVAP Leak Monitor Pinched Hose found

WHEN MONITORED
Immediately after a cold start, with ambient temperature between 40°F 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
LDP must pass stricter EVAP system test first. No air flow through the evaporative system if 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 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 bound 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