Car has 66,500 miles and threw the code the first time right at 66k. The car keeps throwing this code dispite my efforts to find the problem.

I have checked the MAF for cleanliness, resistance and voltage. It seems good.

I have looked at the vaccum lines and I can't find any leaks. I even sprayed carb cleaner around the vaccum lines and the intake to see if I could detect anything.

I have run almost a full tank of fuel with Injector cleaner in it.

I was thinking of checking the O2 sensor but I can't find any good (read as simple) instructions for doing this.

Other than the O2 sensor, is there any other things to check prior to taking it to the dealer?

 

Just got an extended warranty notice for the Crankcase Oil Trap and Ventilation Hose. The notice also states the Check Engine Light may illuminate.

If this failed could it cause my rich condition bank 1 P0172?

I'll post the results when the car goes to the dealer next week.

 

Hopefully the final update on this. Dealer found a dirty throttle plate and associated it with the K&N filter. I have a hard time believing that. All I have read about K&N leads me to think they are just trying to sell Volvo parts at the dealer.

They also found the part that just had the warranty extended on to be in good shape.

They cleaned the intake parts, put in a new filter, and upgraded the ECM. We'll see if the light comes back on. I still have the K&N and will probably use it again, unless I find documentation to the contrary.

 

broken pcv hose from the oil trap to the head, dirty throttle and ecm upgrade

 

They didn't find any broken lines. Just the dirty throttle plate and ECM upgrade. The Oil Trap and Hose Assembly has an extended warranty on it but it was found to be OK and didn't get replaced.

 

Is it the accordian type hose?

 

I don't know which hose the warranty was talking about. They didn't replace any hoses. Just the items listed above, and the light has not returned.

I really think it was the ECM upgrade. I can't see why a dirty throttle plate would give a code that is a generic code (system rich bank 1). From what I saw taking the MAF out and looking at the intake, it really wasn't that dirty. I have a hard time believing that I am the only one using a K&N filter that has had the problem. Like I said before I doubt it was the K&N filter. More people would be complaining about dirty intakes if the K&N was the problem.

 

Cleaning the throttle is part of the bulliten