Ok I have a 2007 F150 that started to run rough last Saturday. It seem to run better when the A/C was turned off, but later in the week it started to run rough all the time. A month or so I replaced the spark plug and boots. The fuel filter was replaced about the same time. Mass air Meter and throttle body have been removed and cleaned. No codes at all, I purchased the two up steam 02 sensors and I got the driver’s side in and I got the passenger’s side unhooked, removed and the new one screwed in, but cannot get the new one plugged in. Any ideals of a way to get to it, so I can plug the new one in? Then any ideal of what to do if this does not fix the rough idle?

 

Well got it hooked up after buying Crescent Double-X Long Nose Pliers Set.
Truck is still running rough at low RPM. The truck idles at 620 with out A/C and 650 with A/C. is this about right?

 

If it isn't throwing a code/s, you'll be chasing it. One thing that may help in diagnosing the problem is to remove each injector connector one at time while it is idling. The engine should change as each is disconnected indicating it's running on that cylinder and should be pronounced since it's idling rough already. If you get to a cylinder that doesn't induce a change, you can narrow it down to fuel (injector or driver), ignition (COP, Boot or plug) or compression (Rings, burnt valve or other mechanical problem) on that cylinder. BTW, how many miles?

Disclaimer: This is to aid in diagnosis only and is not a declaration that this is your problem.

 

Sorry for not listing the mileage. It has 103,000