All right, it's my turn to fight these codes.

First off, I have already installed new OEM gas cap and evap/purge valve.

This started as a P0440, then P0442 added to it a couple weeks ago. I am getting both codes now and they come in immediately after I clear them, as soon as I start the engine. To help me with the diagnostic, I unplugged the evap purge valve and then I got a P0443, so I believe that valve is good.

I think my next step is to get a smoke machine and start digging further.

So here is my question:

-where exactly do I hook the smoke machine? To the large pipe that connects to the purge valve?



This is for a BMW 2003 X5 E53 4.4i M52.

Thank you very much!