i have a 99 f-150 4.6l i put a rebuilt 99 grand maquis 4.6l motor in it the code p0153 keeps coming up i put the new o2 sensor in but it still idles really rough and the light keeps coming back on i dont know what else it could be please help

 

Make sure the sensor got pluged in all the way. Its hard to get to them so sometimes they dont get connected all the way.

 

i already did that and i made sure the all the wires were fine

 

any other ideas??

 

did you replace the sensor with a new one?

 

yeah i put a new sensor in it

 

I see that now in your first post.. What sensor did you use? What Brand? Motorcraft or Bosch are really the only one that work. Motorcraft preferably and you can get them at Rock Auto on the internet for about 50 bucks. That particular code indicates a sensor that is not working properly.

 

i put the bosch one in and it still runs like **** and i keep getting 5 and 8 miss fire and system too lean bank 2

 

could be you have a vacuum leak. check the elbow to the PCV at the back of the throttle body and all other vacuum lines. Whats the code your getting? It must be different then the original code..

 

i bought a vacuum gauge and i was losing all my vacuum at high rpms and i called fords and told them what was going on and they said it was a cloged cat. and sure enough driver side cat was all cloged up and broken so tomorrow ill find out if it is all fixed ill let you know thank you