my 2000 mitsubishi montero sport is burning fuel, you can smell it very bad. what could cause this?

Question

exhaust is blowing grey smoke and there is a heavy smell of fuel. I took it in and they said it could be because the 02 sensors are bad which is causing the fuel to burn more rich. Is this correct? what else could it be?

Answer 1

A faulty 02 sensor is not going to cause grey smoke out the tail pipe. Mechanical condition will cause this condition, One area that should be looked into is the fuel pressure regulator to see if it is seeping fuel into the intake system.

​ Here a fuel pressure regulator diaphragm leaked fuel back into the intake manifold, causing a strong fuel out the exhaust system.