Most likely there is another issue which may not show up on a PCM code scan. The O2 sensor is reading a lean mixture so, the PCM is giving the engine more fuel. Check for vacuum leaks. The PCM will also richen the mixture to compensate for other problems.
The speed sensor is at the top rear of the transmission housing.
the elictronic control sinsor at on a 93 mercury villager
The cam sensor on a 1996 Mercury Villager cost about $35 to $40. The sensor is actually manufactured by a Nissan subsidiary.
the sensor on the 3.3l mucury villager is integrated into the distributor
No, there is not.
There is no such part.
You would fix it by replacing the instrument cluster. The speedometer itself may not be faulty, it is more likely to be a problem with the speed sensor.
on my 1999 ford mercury villager its on top of transmission under the van
If you mean the fuel level sensor it's in the fuel tank.
can you tell me where the knock sensor is located on a 3.3l mercury villager
This is an image. (below)
remove and reinstall