L83 P0172 & P0175 Codes

[Ryan Boudreaux]

I’ve got a 2014 Sierra 5.3 with a little over 164k miles on it that I just picked up about 6 months ago. All I have done to it is cut off the muffler and thrown on a cold air intake.

 

Recently i’ve been throwing p0172/5 codes, but they’ve been coming and going without clearing them. A week or two ago, I cleaned the MAF/MAP sensors and cleared the codes. I’ve had no CEL since, until today.

 

Im not the most well educated on this topic, any advice or things to check would be very appreciated.

[CamGTP]

Check for a leak after the MAF sensor. Those are lean codes, so it's getting in extra air from somewhere past the MAF.

[Ryan Boudreaux]

My reader says the codes are rich bank 1 & 2, not lean, but I will check

[CamGTP]

Yeah, you're right I got them mixed up.

 

But having rich codes on both banks at the same time leads me to a possible MAF issue or at worst you have injector issues on both banks. If you can borrow a MAF from someone to test that theory that would be ideal or just buy a new MAF on a whim to see if that fixes it.