Error code P0172

[osidesurfer365]

My Onstar report just emailed me today, as the check engine light came on and when I called they said it was error code P0172. Anyone familiar with what this is? Hopefully I can fix it myself or does it need to go in?

 

[OR VietVet]

P0172 code:

Basically this means that an oxygen sensor in bank 1 detected a rich condition (too little oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1.

Note: This DTC is very similar to P0175, and in fact your vehicle may show both codes at the same time.

Symptoms

You will more than likely not notice any drivability problems, although there may be symptoms such as a misfire.

Causes

A code P0172 may mean that one or more of the following has happened:
•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 is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
•There could be a vacuum leak.
•There could be a fuel pressure or delivery problem

Possible Solutions

Possible solutions include:
•Inspect all vacuum and PCV hoses, replace if necessary
•Clean the MAF sensor. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
•Inspect fuel lines for cracks, leaks, or pinches
•Check the fuel pressure at the fuel rail
•Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.
•Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible

 

[osidesurfer365]

P0172 code:

Basically this means that an oxygen sensor in bank 1 detected a rich condition (too little oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1.

Note: This DTC is very similar to P0175, and in fact your vehicle may show both codes at the same time.

Symptoms

You will more than likely not notice any drivability problems, although there may be symptoms such as a misfire.

Causes

A code P0172 may mean that one or more of the following has happened:
•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 is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
•There could be a vacuum leak.
•There could be a fuel pressure or delivery problem

Possible Solutions

Possible solutions include:
•Inspect all vacuum and PCV hoses, replace if necessary
•Clean the MAF sensor. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
•Inspect fuel lines for cracks, leaks, or pinches
•Check the fuel pressure at the fuel rail
•Check the fuel injectors, they may be dirty. Use fuel injector cleaner or get them professionally cleaned/replaced.
•Check for an exhaust leak before the first oxygen sensor (this is unlikely to cause the problem, but it is possible

Thanks for the help. Could the error code also be from a loose gas cap? The wife filled it the other day and I realized today when the engine light came on it was loose.

 

[OR VietVet]

You can clear the code and drive and see if that is the case but I doubt it. That would typically set an evap code and your code is not that. But hell, anything is worth a shot.

 

[osidesurfer365]

Is just went off I its own. I'll take it in to my mechanic next week to be safe. Good looking out

 

[OR VietVet]

If your tech will check for free then fine but if the light stays out and you have no running problems then I would not worry about it. If it is out then it is out and no worries right now. If comes back then that means it is what I call a "hard" code and should be addressed.

 

[FuzzyChopz]

If you have an OBDII scanner check the live data and look at your long term fuel trims to in face see if you are running rich/lean. I would guess that it turning off by itself is a good thing though.