2001 Ford Taurus running rough; pulled codes; MAF/O2/other?

Hey car folks,

My girlfriend’s 2001 Ford Taurus (125k miles) began displaying the check engine light yesterday. Recently it’s been running rough, and at a stoplight, it smells like unburned gasoline. Mmm delicious. I went to AutoZone and had the codes pulled. The handy device said: “Fuel trim bank one condition” and “Fuel trim bank two condition.” Unfortunately, the AutoZone attendant didn’t give me the P0xxx codes (one guy said it was against policy, the girl who helped me didn’t know what they were), but combined with the delicious gasoline scent, I’m guessing it’s running rich on both banks.

Searching the previous questions asked, whether rich or lean, it sounds like it’s most likely the MAF or the O2 sensors. Unfortunately, the MAF is ~$200 and the O2 sensors are ~$40 each (isn’t it only the first, though, that controls the A/F ratio?). I’d like to do the right fix first so that I don’t unnecessarily waste money and bruise my knuckles over nothing. Also, I’d like to do the work myself to save money; we’re both “starving” college students.

What do you folks think is wrong, and if it’s the MAF or the O2, which should I do first? Also, is there something I can do to narrow down the problem? Thanks for your help!

Well it’s a shame that they would’nt give you the actual codes.

IF the O2 sensors are reading rich on both banks, the common point that could indeed cause this is the MAF sensor.

Rule number one is dont shoot the messengers/O2 sensors.

Do a google search on cleaning Ford MAF sensor.

You can get the spray MAF cleaner at any auto parts store.

Good luck with it

The conditions for setting a “to rich” fuel trim code (P0175) for example are pretty stringent including,No IAC,No H02S,No TPS,No MAP,No EGR No,MAF,No Misfire codes. The 02 sensor can be contaminated causing a false rich condition to be seen by the PCM (or what ever FORD calls it)

I would look at the IAC first, then fuel pressure,then TPS,then a injector, then inspect the 02sensor. Since it seems you actually do have a rich condition not a falsely reported one I have put this down the list.

You may seek another code scan somewhere else for the exact number(s).