well after my manifold had to be replaced, then the cam timer, now O2 sensor is bad alomg with an apparent biuld up of carbon on the throttle body.

now after a bottle of sea foam to try to clean throttle body, does anyone know how hard it is to change the drivers O2 sensor? is it something that can be done at home easily??

 

Depends on which one and where it is. I know the theory is pretty basic and having the special socket helps.

http://tinyurl.com/o2socketAutoZone
http://tinyurl.com/o2socketsAutoZone2

You have to go slow and careful. Use lots of PB. I don't know how common it is with F150s but my MS6 was known to have the sensors just break off in the bung on the downpipe. Being that this sensor was a ~$300 part, that was no good. Autozone has all manner of O2s for under $50.

http://tinyurl.com/AutoZoneO2sensors

 

I would get motorcraft sensors. Shouldnt be hard... Should be plug n play once you brake the original O2 sensor free...

With the TB having carbon build-up and your O2 sensors shot, sounds like you have a lean system...

 

Lean condition could have been caused by the O2 sensor though. Even if the sensor is bad it might have been reporting values in the proper range so it didn't throw any codes?

 

and maybe its lean cause a volaint CAI i put on?? Its been on for a year at least tho, so wonder why now its a problem.

Do i take the CAI off then??

 

oh sorry....and what problems come from a bad sensor. like me driving it now without it fixed. Will it damage more stuff??

 

Really easy! Did my driver side a while back! Just get a big (forgot what size wrench) with a box end.

 

02 sensor cannot cause a lean condition it only reads what's coming down the manifold and sends that information to the pcm to make fual and air adjustments.
even if the 02 sensor is bad it still will not cause any type of lean or rich codes you will get faults for the 02 sensor not switching properly or heater circuit codes... not lean or rich codes

Your cold air kit can codes lean codes but typically you sould get codes for both banks p0171,p0174
and others possible. if you have a air leak around the air filter going to the t/body could cause your lean codes

 

You can also get a code if your exhaust manifold bolts are broke.

 

Are you sure a bad O2 couldn't cause a lean condition? Anytime you are messing with AFR you can get a lean condition.

If the sensor reports the WRONG information to the PCM (but still in the correct range of valid values) for a given situation the PCM can make the wrong AFR adjustments, resulting in a lean condition.

The O2 can be bad but still in the valid range, hence no CEL for the O2 sensor.