Code Reader - Lean System?

All:

Thought I'd get some advice from the collective: I am getting ODB2 codes P0171 lean system bank 1, and P0174.

Is this an O2 Sensor Problem? Thoughts?

-Doug

Two other possibilities are::_wrench:

Intake gaskets

Clean MAF sensor

Another thought, I had the same codes & thought for sure it was intake gasket related.
I replaced my intake gaskets (which were visibly cracked) only to throw the same codes after putting everything back together.
A little more digging & I found that the little sensors in the MAF were covered in a sooty residue from K&N oil. A quick blast with some MAF cleaner & I've been CEL free for almost a year.

Mine started with the same codes soon after I got it. I found vacuum leaks around my fuel injectors. I could hear it sucking and could almost stop it when I moved the fuel rail around (Loosened the bolts that hold it a bit). I replaced the 'O' rings and problem solved for about 4 months, but now it's back again. :(
At this point mine goes off every few weeks, for a day or two, then right back on (Usually when slowing down or coming to a stop), so I think it's O.K. while driving? :confused:

Looks like we're in the same boat, I've just been ignoring it while the weather is freezing cold (which might be part of the problem?????).

Intake gasket or EGR gasket will cause these false codes.

Its allowing unmetered air to bypass the air sensor.

John C.

Thanks to all! I'll mess around with these possible solutions-maybe pickup a new O2 sensor to be safe.