Has anyone replaced ther o2 sensor on their 4.6 ? I have 133k and I know everything is getting tired. I was wondering if replacing the o2 would help in power and mpg. I am not passing any codes now.

 

there are 4 O2 sensors on the 4.6L, 2 upstream and 2 downstream. a faulty O2 sensor can cause the truck to run too lean or too rich. if you experience extremely rough idles, or black smoke from the tell pipe, then you could have an O2 sensor on the brink. they're $50 at autozone, $150 at ford. if you're having a lack of power, try cleaning the MAF, especially if its never been cleaned.

 

Thanks Plug, Will try the MAF cleaning when I get a chance. I think I read somewhere to clean the MAF I should wipe it down with a q-tip and some fuel injector cleaner. Is this correct.
Mike

 

That is correct for the MAF cleaning.

I have a 4.6 L 4x4 w/ abt 96K miles. I replaced my O2 sensors not long ago but didn't notice any real changes to the enigine performance. Did seem a bit quicker on the throttle response, but could be in my head as well.

Get your sensors from AutoZone. Abt $50 and they'll rent you a special puller that may or may not help you in getting your old ones out. I had just about as much success with using a regular wrench since the space to fit the tool in is very tight.

Good luck and have fun.

 

What do you use to clean the MAF?