This is a long story... please help! 2006 Ford explorer 4.0 single overhead 270,000


Last month my radiator went and I took it in to the mechanic since we had 10 feet of snow in my driveway. While it was there he said I had a timing chain issue and a gasket leak. I replaced all four time chains, Intake Mainfold gasket, cover gasket set, oil pan gasket (upper and lower), oil cooler, and radiator. (4.5K dollars later) The mechanic said come get her. I did. She was running lean so when I got her home and she pulled bad codes for 2 O2 sensors, TPS, evac purge solenoid and a EGR Valve. Still have snow and baby due in a month so I took the car back instead of doing it myself. He said those were fine but that the vent solenoid underneath was bad. I said are you sure? I've thrown those codes before for the bad O2 and then they would go out. It is time to change them. He said they are fine. Well... picked the truck up and I am now throwing another code (p0430). He said I have a bad CAT. Is it or could the O2 sensors be bad enough to be affecting the CAT? I've put 5k into my truck. Buying a new one now isn't an option besides, the body is solid and the suspension work is all completely new from last summer when I did it. I am tired of the two mechanics in this stupid place charging me and yet my car doesn't seem to work. Does anyone have some suggestions on what to change? Should I go ahead and do the O2 sensors and stuff or is my CAT possibly really bad and I should just replace it. I have never pulled this code in all my time of owning this truck and I got her when she only had 95K. I'm attached.

 

for the p0430 to run and set the 02, evap, secondary air systems monitors must run and pass. if faults in these systems were present, the p0430 test would be suppressed. If the faults were repaired the p0430 would now run and fail.


When dealing with 02 sensor repairs, I always inform my customers of this to prevent them coming back and saying I did not fix it properly when the new dtc sets.


the ecm views the cross counts of the pre and post cat 02 sensors. When they are switching at near the same rate it determines the cat is doing nothing and is bad. Most of the time it is the cat. Don't cheap out and buy a cheap cat. It will have low cerium content, the oxygen storing element in the cat...the dtc will just reset.


I would clear all the dtc and see what monitors run, pass and fail. If everything passes but the cat monitor p0430...replace the cats