I have heard this as well but I do not think that this is the issue. The idle issue started immediately after I installed the returned AA computer.
Originally Posted by bigjae1976
I've been told that an exhaust leak with aftermarket headers can cause idle surge and weird idling. The claim was that exhaust air is pulled back up across the O2 sensors between pulses. I guess this is not an issue with the OEM manifolds since the cat is between the precat O2 sensors? I kept burning through gaskets so I just had some V-bands installed.
But my idle still surges a bit but not terrible. I still think the tune is not totally correct.
I plan to get Eurocharged to do my tune in the near future. Remote tuning was such a PIA.
2005 BMW 330i ZHP
Black on Black
AA stage 2.5