2004 BMW z4 3.0i Do I need to buy an OEM cap for the code P0442?

Question

I used an exact-fit gas cap from Advanced Auto Parts, and I still have the P0442 code on my 2004 BMW Z4. Do I need to buy an OEM cap? What else can cause the code? thanks.

Answer 1

Unfortunately, there are many things that can cause that problem, I'm not sure what type of cap you bought, but I have seen some aftermarket caps causing that problem. At this point, I suggest either buying a factory cap or getting the system tested by a tech. Most techs use a smoke machine to find leaks in the EVAP system.

P0442 BMW Code - Evaporative Emission System Leak Detected Small Leak
Read more: https://www.autocodes.com/p0442_bmw.html