Service Engine Soon P0172

[Thub]

The service engine soon light came on today on my 2002 V6. Got the code read and came up with P0172. Truck is running fine, no misfire or running rich. Does that pretty much narrow it down to a bad 02 sensor or something funky with the MAF sensor, or is there something else that can trip that code.

 

[imp]

P-0172- "Mixture too rich, bank 1". Oxygen sensor far end of cat converter possibly bad, or leaking fuel injector, bank 1. The 02 sensors are easily changed, delete code, drive awhile to see if repeats. Injector isolation of one bad one not easy at all, probably replace all 3 on bank 1, better yet all 6. Depends on their age. imp

Edit: MAF has it's own set of codes for probable malfunctions, at any rate, how could it affect only one side of the engine It feeds air to the whole damn thing! imp

 

[Thub]

I realize that It really can't be the MAF since it is only 1 bank not both. My sister told me today that the exhaust really smelled of fuel like it was running rich. I took it for a drive and couldn't get it to smell as bad as she described but it did have a little more odor to it than normal.
So I'm thinking its either a bad injector or bad cat.

 

[Lecke]

Has anyone found out what could cause the P0172 only (P0175 not present). My thinking is that if I have a bad MAF sensor, the computer would trigger a code for both banks, noty just bank1. Also, if it was a bad O2 sensor, it should also read a code related to the sensor. Am I right?

 

[swetrid]

It could be the o2 sensor, Ford had a tsb to reprogram the pcm for rich codes on 2004 model year.

 

[Lecke]

What is confusing is that this started to happen a couple of days ago and I've owned this vehicle for 4 years already. If it was a recalibration issue, shouldn't have happened long time ago already? Tks

 

[swetrid]

This business humbles you, I don't say no to any possibility anymore. I have seen way too many odd things over the years. I would have pcm updated first which I about $45-$75 at most dealerships.