Need to replace my dpfe sensor on my 1999 mercury mountaineer. Where is it, i would like to change it myself

The sensor is on the rear of your engine next to the firewall on the 5.0 looking at the egr valve just to the right of it, has two small bolts holding it on and holding the stamped steel bracket for its up against

I believe the sensor that you are looking for is on the drivers side of the engine. If you have a 4.0 SOHC engine or a 5.0 engine the wiring will be the same. You will have a brown with a white tracer, a brown with a light green tracer, and a grey with a red tracer to the sensor. If you you have a 4.0 EI then you will have a Brown with a white tracer and 2 brown with a light green. If you follow the 2 tubes coming up from your exhaust manifold you should be able to locate your sensor it will have to tubes or hoses going to it from your exhaust manifold. Good luck.