PCV System Monitor

WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2004 Mercury Sable, 2004 Mercury Mountaineer, 2004 Mercury Monterey, 2004 Mercury Marauder, and 2004 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

The PCV Monitor consists of a modified PCV system design. The PCV valve is installed into the rocker cover using a quarter-turn cam-lock design to prevent accidental disconnection. High retention force molded plastic lines are used from the PCV valve to the intake manifold. The diameter of the lines and the intake manifold entry fitting are increased so that inadvertent disconnection of the lines after a vehicle is serviced will cause either an immediate engine stall or will not allow the engine to be restarted. In the event that the vehicle does not stall if the line between the intake manifold and PCV valve is inadvertently disconnected, the vehicle will have a large vacuum leak that will cause the vehicle to run lean at idle. This will illuminate the MIL after two consecutive driving cycles and will store one or more of the following DTCs: Lack of O2 sensor switches, Bank 1 (P1131 or P2195), Lack of O2 sensor switches Bank 2 (P1151 or P2197), Fuel system Lean, Bank 1 (P0171) or Fuel System Lean, Bank 2 (P0174).

For additional PCV information refer to POSITIVE CRANKCASE VENTILATION SYSTEM .