Hey guys been awhile since I posted on here but I've run into a problem with my Ralliart.

I just changed my spark plugs from the stock DILKR7B6 to a new set of DILKR8B6 as i read the colder ones are better for increased boost. I then replaced my old ratty AEM dry cone filter for a brand new one. All of a sudden I'm getting terrible fuel economy, significant smell of gas in vehicle and the P0171 code.

Now I am trying to figure out who is the cause of this. My custom tune already accounts for a short ram intake but not for the colder plugs so I figure those must be the problem but the colder plugs are reducing my knock under load when in Normal mode and cost me a pretty penny so I really don't want to go buy DILKR7B6 and it not fix the problems.

Any ideas? I might clean the MAF today and see if that helps.

Mods: SRI, Turboback Exhaust, EVO X BPV & IC, IC Pipes, Fuel system fuses, custom e-tune.
Unfortunately my AFR gauge broke last year and i haven't replaced it.