2001 QX4 - EVAP readiness never ready, P0171 code

[attofarad]

My GF's 2001 QX4, ~109k miles.

After resetting the error codes, the EVAP readiness never became set. All others did, over a few days.

She's been getting P0171 for quite a while. Didn't find any intake/vacuum leaks, checked the MAF voltage at the connector for various RPMs and looks okay to me. At one time, also got P0174, but that went away and never came back after reset. After unplugging and cleaning the MAF, got misfire P0300 a couple of times, which stayed reset okay. I think she got a P0300 one other time since then.

Any ideas?

Gary

The driveability has its good and bad days. Sometimes seems just great, and sometimes just no getup and go. Could this be the front right O2 sensor? Symptoms seem sorta like MAF to me, but that seemed to measure okay.

Modified by attofarad at 6:09 PM 9/12/2007
Modified by attofarad at 6:10 PM 9/12/2007

[fueler]

Ahhh dont u love the 3.5

Hope this helps zerothread/135082