code p0171 plz help before i spend $100 for the maxima maf

[thaomyt]

I had clean the maf twice with the maf cleaner then clear the code, but it came back after a few hours. no vaccum leaks
thanks

[Towncivilian]

If you have a suitable scan tool you can measure mass air flow sensor signal to see whether it's within the specified range (see page EC-299). But other than that, you can't test the MAF sensor (except its wiring, but if its wiring was bad I'm almost positive it would be throwing a MAF sensor code).

[ARKQX33V6]

A lean condition can be:
fuel starvation
injectors not opening properly, may be fouled
weak fuel pump,
plugged fuel lines
a MAF sensor deteriorating, voltage wrong
Even vacuum leaks

Since you have cleaned your MAF sensor the sensor possibly reads dissipated temperatures wrongly thus indicating incorrectly.

Check carefully the sensor and wiring and leakage in the plenum and conduit system.