Getting a P0174 error on my '04 A8. I'm assuming this code on the A8 is the "Fuel System Too Lean (Bank 2)" code. Which cylinder bank is denoted as bank 2 on the A8? Any common issues that would cause this - i.e., specific vacuum leaks, etc.?

l8r)

 

That's the driver side, #5 - #8. Haven't heard of a common cause/problem...but vacuum hoses would be my first guess...just a guess, though...haven't ever had that code.

 

16558
P0174
Fuel Trim,Bank2 System too Lean

Like silverd2 said, being lean on one bank generally boils down to a vacuum line. Its probably about time to go thru them all and replace as many as you can see thats damaged or frail looking.

 

Good news, I took a look, and the clamp holding the MAF to the intake snorkel had wormed its way loose. Tightened it up, and the CEL cleared after about an hour's worth of light driving. All the vacuum hoses still look in good shape.

l8r)

 

Must have happened after the last oil change service, the MAF has to be taken out to remove the air box.

 

^ Probably, in which case I was the culprit. Although, ironically I fixed the MAF to begin with, since whoever did the oil change before me, didn't have it aligned properly (although they did have it clamped down.

l8r)