WE HAVE A 2002 F150 4.2L V/6 THAT IS SETTING CODES P1131 & P1151 LEAN EXHAUST. WE REPLACE O2S AND DECARBONED ENGINE. THE ENGINE HAS VERY INTERMITTENT MISS, TO SLIGHT TO DETECT WHICH CYLINDER IT [...] WAS A HISTORY EGR CODE WHEN IT CAME IN.(customer installed a... Login to read more.