Purge Valve

WARNING: This page is about a different car, the 2017 Jaguar XJ, 2016 Jaguar XJ, 2015 Jaguar XJ, 2014 Jaguar XJ, and 2013 Jaguar XJ. However, it is still accessible from the selected car via links, so may be relevant.

The purge valve is located on the left side of the engine, below the ignition coils cover. The purge valve is a solenoid operated valve which is closed when de-energized.

A vapor pipe is routed from the purge valve to the inlet of the supercharger. The purge valve is controlled by the ECM and is operated when the engine operating conditions are correct to allow purging of the Evaporative emissions canister.

A vapor pipe, which is routed parallel with the fuel delivery pipe along the left underside of the vehicle, connects the purge valve to the Evaporative emissions canister.

The purge valve is operated at 10 Hz by a Pulse Width Modulation (PWM) control ground from the ECM. At this high frequency, pulses of fuel vapor flow into the intake of the supercharger in an almost continuous flow. The valve operates at a duty cycle of between 7% and 100%.

Atmospheric pressure in the Evaporative emissions canister is higher than the pressure at the supercharger inlet under all throttle settings and engine running conditions. This pressure differential allows vapor to be drawn from the Evaporative emissions canister, through the open purge valve and into the supercharger air intake.