How many PCV valves does a 1997 Mercury Mountaineer have?
( 1 ) PCV valve for your 5.0 liter / 302 cubic inch V8
The Owner Guide shows Motorcraft EV-152 and fordparts.com shows Motorcraft
EV-152-D as the part numbers
There are a total of ( 4 oxygen sensors ) according to the engine wiring schematic for the 1997 Mercury Mountaineer in my Haynes repair manual ( 2 oxygen sensors are " upstream " sensors used by the PCM to adjust the air / fuel ratio of the engine ) ( 2 oxygen sensors are " downstream " sensors / catalyst monitors )
For a 1997 Mercury Mountaineer ( 5.0 liter V8 ) ( there are a total of 4 oxygen sensors , 2 sensors that are used with the PCM to adjust the fuel ratio that are nearest the engine on both sides , and 2 sensors that are also called catalyst monitors because they are in the exhaust after the catalytic converters ( downstream sensors ) On the passenger side of the engine in a Mercury…