lean bank codes, can't find the leak.

[petebert]

05 x5 3.0i 120k miles. Smoke tested it and found the DISA leaking. Decided to replace the o-ring, found that a previous owner put a Chinese DISA on it. Replaced the o-ring and the codes still came back. Decided to do a better job removing the old gasket material and tried again, codes came back and found smoke leaking from it again. Decided to just replace it with a OE BMW DISA. Codes came back but now I can't find any smoke.


Considering trying a new lower intake hose. Theory I'm going with is that the smoke tester runs at very low PSI but actual driving conditions will draw more pressure and expose a crack in the rubber.



Anything else I can check? If it helps I have the Schwaben scan tool so I could check the readings from individual sensors. Although I'm not sure what values would be in range, say if it's a MAF or o2 sensor issue.