laserred02

Hi guys i'm new to the forum, although not new to working on a car. the problem is my 02 V6 is shooting trouble codes p0172 and p0175. about a week ago it was shooting p0401 i believe which was an egr code. I replaced the egr valve, and then the egr position sensor and that problem seems to have gone away. however i still get the p0175 and p0172 codes (running rich on bank 1 and bank 2) any ideas?? oh i have 68xxx miles.

thanks,
pat

WhiteStang01

A code P0172 and P0175 may mean that one or more of the following has happened:

* The MAF (Mass Air Flow) Sensor is dirty or faulty.
* There could be a vacuum leak.
* There could be a fuel pressure or delivery problem
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laserred02

Thanks for the reply, I thought the same thing about the MAF and I pulled it off and cleaned it last night using contact cleaner. I also pulled off the throttle body and cleaned it out. i have been told that the 02 sensors could be acting up or the fuel pressure regulator, is there a way for me to test those things. again thanks for the help.

WhiteStang01

Well you will need to check for fuel pressure at the service port in the fuel rail. The pressure should hold with the key on and engine off if it doesnt it may be a leaky fuel pressure regulator. Also you want to check the vacuum hose to the regulator to see if there is fuel in the hose that usually indicates a leaking diaphram. As far as checking the 02 sensors you will need a scanner or a osiliscope and see if the values of the 02 sensor and see if the volts are fluctuating. Good luck [sm=badbadbad.gif]