sjwolf

Service engine soon lamp lit. Searched web ... probable cause vacuum leak ... looked for a loose or leaking hose .... PCV hose was disconnected from the intake manifold .... slipped back into place. We don't drive the truck often, code has not yet reset ... had Auto Zone pull the codes p0171 & p0174 were the results .... could this disconnected hose have caused these codes to be triggered.

sjwolf

Also how long does it take for a code to reset ... after fix ?

TheUnforgiven71

That can cause the issue but you won't know for sure until you clear the codes and check again after driving it around for a good while again

Jbrew

You should reset, -disconnect the battery for 1/2 an hour or so. IF that was the cause, the DTC won't be back. It most likely was, you should always reset after servicing anything to do with air metering.

Warspite

Lean codes (171 and 174) take 20 ignition cycles to set (shows up as "pending"). Disconnecting the battery will reset them. I don't think the reverse/pending is true - meaning that a "clear" is pending. So, the battery disconnect will definitely clear ALL codes (let's hope those were the only 2 in history).

sjwolf

Reconnected PCV hose to manifold, reset codes (battery disconnect / reconnect). So far I've driven 60+ miles and no errors. Thanks for input.