I just installed my K&N typhoon, and a XTC dwnpipe/w/hiflow cat and car ran fine on the first day. Next day i start it and CEL appears and whenever i idle, car sputters a little. Almost wants to stall? Do i just need a tune, or would it help to replace spark plugs as well? Car has only 57,000km on her, so im lost right now. Any help would be appreciated....

 

MAF...check it and silcone connectors

 

I would say maf is off due to the intake which shouldnt be but you probably have a 420 code due to the high flow cat. simple tune will take care of all.

 

Winner. Intake is bigger than stock, so the engine is getting more air than the MAF is telling it.

Short answer: You're running lean. Get tuned.

 

give Trifecta a call.