Vovovovan

my car started to throw po172 and po175 (system is running too rich on both banks) i put 2 brand new 02 sensors but that didn't do anything, it's still throwing the codes. what can be a possible problem? all the mods are in my sig, basic bolt ons.

WhiteFoxGT

How is the car running?

Could be a clogged up intake, dirty MAF, high fuel pressure, bad PCV, oil over-full...etc..

I'd start giving the car a thorough visual inspection and make sure everything is plugged in and nothing is blocking the motor from breathing

Vovovovan

the car runs pretty smooth, i just cleaned the filter a week ago. how do i check if the intake is clogged?

CAMDUP

did this start after you cleaned your filter ?

Vovovovan

maybe, yeah like 2 or 3 days after it

CAMDUP

theres been times that the "fresh wet oil " on the filt will get on the MAF (the actual sensor itself) .....try to clean your MAF....autozone/advance auto they all sell a spray MAF cleaner

Brute03

+1 on cleaning your MAF, just spray the wires down with electrical parts cleaner.

Xemeth

The O2 sensors might not have been the problem.

Also, did you clear the codes after changing them, and then the light comes back on?

WhiteFoxGT

Like 95% of the time its NOT the sensors. What are the odds that both 02s went bad at the same time? Slim and none. Its funny how people are quick to throw 02s on when they set a code.. When the 02s set codes, they are simply doing what they are designed for; monitor engine performance.

Most likely a blockage in the intake duct or debris/oil on the MAF

PROMETHEUS PRIME

I second the MAF being the problem with oil from the filter on it.