• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Fiesta ST Forum and Fiesta ST community dedicated to Fiesta ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Fiesta ST Forum today!


CEL after installing a drop in K&N air filter

Messages
31
Likes
5
Location
Naples
#1
About a week and a half ago I installed a drop in K&N air filter. After driving it a few times I noticed a CEL. I went back and checked the screws in the airbox and they are all tight. The car runs real smooth after installing it in also so what gives?
 


Messages
487
Likes
420
Location
Boston
#2
Check to see if you may accidentally tugged, disconnected or loosened any vacuum lines during install.
 


Messages
106
Likes
32
Location
San Diego
#3
Other cars have had problems with K&N oiled filters from having excess oil migrate onto inlet sensors and screwing them up. One case I know of, factory warranty was denied because it was a fault from a non OEM component. Not a Ford though -- your problem could be different.
 


OP
J
Messages
31
Likes
5
Location
Naples
Thread Starter #6
I'm gonna get her scanned. I read up on K&Ns website where it says some vehicles might have a CEL come on due to more air coming in and the computer has to relearn the air flow. And supposedly it will go away after 20 to 30 cold engine start ups. Don't know if that's true or not.
 


CanadianGuy

4000 Post Club
Messages
4,097
Likes
945
Location
Southern Ontario
#7
Btw check the connector for the mag sensor making sure the latch is locked. And for those looking for a dry filter ramair has a foam dry filter and mountune a panel filter is considered an dry filter.
 


Truth in Ruin

1000 Post Club
Messages
1,177
Likes
956
Location
Lincoln
#8
Btw check the connector for the mag sensor making sure the latch is locked. And for those looking for a dry filter ramair has a foam dry filter and mountune a panel filter is considered an dry filter.
So mountune's filter is a dry filter?
 


neeqness

1000 Post Club
Messages
1,398
Likes
166
Location
LA
#10
I have the Mountune air filter and no CEL so far after about couple months use and nearly 10k miles. No other engine mods though and mine was not oiled.

Sent from my LG-H918 using Tapatalk
 


jmrtsus

1000 Post Club
Messages
1,531
Likes
1,171
Location
Ooltewah
#11
I doubt the filter is causing it..........Mountune has sold thousands of them and I have never heard of a CEL on the MP215. Wonder what the code is???
 


haste

1000 Post Club
Messages
1,222
Likes
1,265
Location
Eastern
#12
I doubt the filter is causing it..........Mountune has sold thousands of them and I have never heard of a CEL on the MP215. Wonder what the code is???
I agree, it may be just a coincidence, but it is also possible something was disturbed during the install.

OP, do you have a knowledgeable friend that could take a look at your intake system? Also, you could take the car to a local auto parts store(Autozone, Advance or O'reillys) and have them scan the code for free.
 




Top