Why is the check engine light blinking in your 1999 Mercury Courgar Already change 2 sensors?
Maybe the sensors you changed out were not the problem. Post what the symptoms were, what the codes were, and why you changed out what sensors you did. Sometimes errantly the wrong part is diagnosed as being defective, like having low fuel pressure and people spend $500 for fuel injectors when in reality it was a clogged fuel filter for $10 Some cars take a few starting cycles or cycles of driving before they reset the check engine light. If you had someone read your codes, normally they have the ability to turn off the check engine light. If you replaced the incorrect part(s) then your check engine light will remin on until the part casuing the fault is replaced. I hope the parts you replaced were the problem and it's just a matter of havign the check engine light turned off. If not, repost and maybe we can direct you. Todays' engines are not like ones of old where you can throw parts at it and "feel" you got it fixed. It's either fixed right or the check engine light is there to remind you it isn't.
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…