Hi I have a 2002 Mercedes C320. My check engine light went on and I was going to take it straight to a mechanic but my friend said I should first just by an ODB reader and check myself, so I did. I got codes P0131 and P0171 (orange alert meaning fairly urgent).

P0131 means the O2 sensor is low
P0171 means the engine is too lean

I don't know much about cars, but I do know that when I drive it now, the motor is louder and you can hear an air flapping sound.

My friend says I don't have to do anything and the car will run just fine. He says I should just order an O2 sensor and repair it myself. The only thing that I have to worry about is if I have to pass a state inspection.

I have some big road trips ahead and I want to make sure it's true that I can drive as much as I want with it this way.

So can anyone concur that he's right and the car should run just fine and that I just need a new O2 sensor when I get a chance to buy one? Or is this something more urgent? Thanks!

 

your fuel economy might be off. it could be o2Sensor or air mass meter , or has a vacuum leak . your car has 4 O2 sensors so code should tell you the one to replace. you should not have a big problem if you drive like this except for check engine lamp on

Jerry