Can the P0449 Emission code cause a random misifre?

Question

My 2006 Tahoe 4.8L show DTC code P0449 for Emission Evaporation System Vent Valve. I have been having a random misfire as well. Idle is fine but the misfire tends to happen when accelerating.

Answer 1

HI there

This will not cause any running issues at all. For the random misfire I would start by checking the ignition coils and the fuel pressure. Since the issue happens under acceleration, that usually rules out any type of vacuum leak causing the issue. The coils and fuel pressure can cause the problem under load. As well as the mass air flow sensor.