Just installed a Calan catch can with two -10 fittings and lines to the catch can, and one -12AN line to the intake/slash cut AFTER the MAF. PCV was not touched, and car idled perfect before the catch can, and still does when i disconnect it from the intake. It seems it is bypassing airflow that the MAF isn't seeing and f*cking it up. Not only does the car surge, but the AFR's fluctuate significantly. Anyway to fix this?

thanks in advance.

 

Make sure the catch can drain is closed

 

It is.