Steve is right, its running lean. if after cleaning the MAF, replacing the PVC and cleaning the Throttle body and plugs, if the code comes back, you will need to get a new MAF. there only about $80 and you can install that yourself. http://www.4x4wire.com/toyota/maintenance/...ntenancep5.html ALSO, at about 100K miles you will want to change the O2 sensors.
Just wanted to say HI, name is Ric and Im in Denver,co. got a 99 4Runner with a few mods, that a few of us go 4wheeling just about every weekend. If you have any questions, feel free to ask.