What causes trouble code p0172?
What causes trouble code p0172? A Thermostat stuck in the open position can mechanically cause a code P0172, especially in cold climates. The engine won't warm up, preventing it from going into "closed loop" fuel control. Ignition misfires, like mechanical misfires, cause puffs of oxygen to keep hitting the Oxygen Sensors. What is causing a p0174? There is a lot of different things that could cause the P0174 code. The most common reason for the P0174 code is a faulty MAF sensor or a vacuum leak somewhere. It can also be low fuel pressure-related problems like a weak fuel pump...