Will the stock mass air flow sensor throw a code in a injen intake I keep getting p0171

 

The MAF itself may not be your problem. When you get an aftermarket intake, it changes the flow dynamics of the intake and the MAF needs to be recalibrated. I never got a code for my intake but I know people who have. Rule out any other potential problems before you blame the intake.

 

Is the p0171 maf frequency fail high? Or something like that?

 

It's "system too lean."

 

Have a K&N cai on, no codes, but it seemed to take a while for gas mileage to recover.