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P0174 Code: Fuel System Trim Lean

JohnnieMo

SM 2017
PM 2014
SM 2013
Full Member
Joined
Jun 2, 2011
Messages
905
Location
Calgary, Alberta
So I got a check engine light on my supercharged 2008 Avalanche this week. The code reader says it is a P0174 fuel system lean code. Here is he report.

https://drive.google.com/open?id=0B3HPOJdKc_m0djRwVXBQUklWMXhIUC1Oby1nQy1iMDdjcThN

Upon some research this code basically points to a vacuum leak or could also be an exhaust issue. (bad back pressure ). The shop that did my blower says they often see this when cats go bad.

Upon inspection i found this:



I jiggered with it a bit and the code went away. I'm going to get a second opinion but this cracked hose is my top suspect.

Any insights are appreciated. I'm mostly documenting this for reference. 

 
I think you are dead on track, try sealing or replacing it.
 
Yea by looks of it your definetly pulling in air past the MAF sensor...

You could spray whatever people use to check for vacuum leaks around it but generally if you see something cracked that bad it is leaking and needs replaced.

 
redheadedrod said:
Yea by looks of it your definetly pulling in air past the MAF sensor...

You could spray whatever people use to check for vacuum leaks around it but generally if you see something cracked that bad it is leaking and needs replaced.
I tried spraying carb cleaner but couldn't get anything to react.  However the code is gone for a couple days.  I didn't actually find a hole in the crack, but I want to replace it anyways.  It's possible one of the clamps became loose also. 

While I was in there I saw my MAF looked like it could be cleaned.  Are there good directions on how to do that?
 
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