When I bought my car it had one of those crappy k and n typhoon intakes on it. I finally got my hands on an oem set up out it on and now the car won't idle. The only code I'm getting is p0171 (bank 1 lean). Which points me twords a vacuum leak but I can't find any with carb cleaner nor do I hear any. I have swapped in a different maf with no change. It just baffles me how changing an intake can cause me so many problems. I even tried to put the k and n back on with no change. I've reset the ecu several times and even tried a different tune with my Cobb. Am I missing anything obvious here?

 

Forgot to add the car is completely stock except for Meghan Racing Test Pipe and Exhaust.

 

Check that the VFAD nipple is blocked off. It is on the plastic intake close to the oil dipstick. Little nipple should be plugged. Check the MAF o-ring as well

 

Wow good call the vfad nipple was open. My only question is why was it never a problem before now? As far as I know it's never been plugged since I have owned the car.

 

LOL...hard to say. Likely the car was able to compensate before you went back...maybe because the K&N screens suck. The OEM screens and intake are likely much more accurate at idle. The differences in the intake tube dia and a few other issues could have played a part as well

 

Just got back from a spirited drive. The idle is solid, and noticeably smoother than the other intake. The intake temps are a good 60 degrees cooler now also. Thanks for the quick reply and for the help.

 

lol. Ouch. If ever there was an argument against the K&N intakes...

Glad you got her fixed!

 

165 degrees on a 74 degree day.