Hey Scotty,
I have a too rich code on my 2005 Acura TL auto trans with 138,000 kms. I have replaced the air filter, pcv valve, adjusted the valves, new spark plugs and o2 sensors appear new (but I didn't change them, previous owner may have). I cleaned out the EGR as well. I've read Acura forums but there is no one answer for the problem, and I seemed to have tried them all. What else could cause these too rich codes?
Thank you.
You may also try here:
https://www.obd-codes.com/p0172
https://www.obd-codes.com/p0175
From those sites:
- The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters can cause the MAF to become dirty if the filter is over-oiled.
- There could be a vacuum leak.
- There could be a fuel pressure or delivery problem
Also, did this happen recently? Are the 02 sensors OEM?
Thank you for the response.
- The MAP sensor should never be dirty as it goes through a snake channel but I cleaned it anyway a few weeks ago with no difference.
- Wouldn't a vacuum leak cause a lean situation?
- I have not checked the fuel pressure or delivery.
- I don't know if the sensors are OEM. Two appear to be changed, but I can't tell if the ones after the cat have been changed as they are hidden at the bottom of the engine bay.
- This issue is fairly new, however it has been idling a little rough for a year or so.
I also forgot to mention there may be a misfire as the check engine like was blinking (happens at a stop light when sitting at idle).
Forgot to update, I adjusted the valves and it fixed the problem