Maf? p0171 p0174

my 2011 z71 ltz silverado cel came back on this morning after changing maf a couple weeks ago. a couple weeks ago it cel came on had the codes ran came back p0171 maf. switched it and reset it by pulling the battery. this morning it was back so I had the codes ran again. this time p0171 and p0174. brand new sensor k&n filter brand new. I tried pulling the sensors connection while running and truck stays on connecting and disconnecting. any ides what it could be maybe bad wire harness??

We tested K&N filters at the company I retired from.


If you want to keep birds and chipmunks out of your engine, that’s the air filter to install.


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What Causes the P0174 Code?

The most common causes of the P0174 code are the following:

  • Vacuum leak due to damaged intake manifold gaskets or punctured vacuum and positive crankcase ventilation (PCV) hoses
  • Malfunctioning mass airflow (MAF) sensor
  • Clogged fuel filter
  • Failing fuel pump
  • Clogged fuel injectors
  • Failing fuel pressure regulator
  • PCM issues (e.g., software in need of an update)
  • Worn-out oxygen sensor
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trying to narrow it down. I know when you have the vehicle running (most vehicles) disconnecting the maf will stall the engine. when i disconnect it stays running connecting and disconnecting while running. with a brand new maf sensor.

If you unplug the MAF sensor, the computer will substitute the lost signal with a default value programmed into the computer to keep the engine running.


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