K&N Air Filter
Senior Member
Joined: 04-09-2010
Posts: 192
From: Northern Virginia
the LNF is a very finicky engine/ecu setup...... a simple drop-in K&N filter will allow a good bit amount more air into the turbo (past the MAF) than the factory paper filter, so then the ecu trys to compensate with fuel, throwing the fuel trims off and causing the car to go into what i'd like to call "retarded mode" and throws a CEL. put your factory filter back in and it'll be fine again. in order to run a K&N filter, it's a simple fix....... custom tune.
P.S. Gonna peel that K&N sticker off also...
Senior Member
Joined: 10-04-2010
Posts: 724
From: Delaware
Yep, going into "retarded mode" about every 100 miles or so. Cleaning the MAF I'm sure was a nice idea but did nothing. Paper is going back in and hope for back to normal. Perhaps having an auto trans isn't helping either. Just a note for other auto SS owners, I'm not sure that there was even a noticeable difference anyway. If you have to convince yourself that there is a performance gain then is it really worth $50?
P.S. Gonna peel that K&N sticker off also...
P.S. Gonna peel that K&N sticker off also...
4 mods i believe are best for the HHR SS (no matter what trans)....
catless downpipe
new hot side charge pipe
k&n filter
custom tune
be sure to purchase a pack of Depends.... because once you do all these, you'll be crapping your pants.
Senior Member
Joined: 10-04-2010
Posts: 724
From: Delaware
Senior Member
Joined: 04-09-2010
Posts: 192
From: Northern Virginia
I know, it's a warranty thing...
yes the filter is worth it, but you just have to get a tune also to get the full benefits from it.
4 mods i believe are best for the HHR SS (no matter what trans)....
catless downpipe
new hot side charge pipe
k&n filter
custom tune
be sure to purchase a pack of Depends.... because once you do all these, you'll be crapping your pants.
4 mods i believe are best for the HHR SS (no matter what trans)....
catless downpipe
new hot side charge pipe
k&n filter
custom tune
be sure to purchase a pack of Depends.... because once you do all these, you'll be crapping your pants.
Senior Member
Joined: 01-13-2008
Posts: 4,708
From: Washington State, where it rains
Im sure Ive read here that There wasnt a whole lot to be gained from either K&N or CAI systems..Its hard to believe a 1 to 3 hp gain would be enough to mess with the parameters....for all practcal purposes the Napa Gold air filter flowed just as well and never threw a code.....
Senior Member
Joined: 04-09-2010
Posts: 192
From: Northern Virginia
Im sure Ive read here that There wasnt a whole lot to be gained from either K&N or CAI systems..Its hard to believe a 1 to 3 hp gain would be enough to mess with the parameters....for all practcal purposes the Napa Gold air filter flowed just as well and never threw a code.....
. Thanks Woody!
Senior Member
Joined: 10-04-2010
Posts: 724
From: Delaware
understandable. if you don't already have it..... there's nothing wrong with rocking a GMS1 for a while.
the reason some people don't throw a CEL is because either they're lucky or stock.... when the LNF is stock, it still has the "learndown" feature which no matter what mods you to do the car, it'll still put down factory power and the ECU will adjust for the mod and like it's not even there. but i'm sure you knew that.
but once you add the GMS1.... the "learndown" feature is removed, so putting a performance air filter in will throw off the fuel trims enough to throw a CEL or make the vehicle act up. once that happens the only way to make the ECU adjust to it is to custom tune the parameters. and once it's custom tuned for the filter.... it's more of a 8-10whp depending on the tune, making it worth it.
Im sure Ive read here that There wasnt a whole lot to be gained from either K&N or CAI systems..Its hard to believe a 1 to 3 hp gain would be enough to mess with the parameters....for all practcal purposes the Napa Gold air filter flowed just as well and never threw a code.....
but once you add the GMS1.... the "learndown" feature is removed, so putting a performance air filter in will throw off the fuel trims enough to throw a CEL or make the vehicle act up. once that happens the only way to make the ECU adjust to it is to custom tune the parameters. and once it's custom tuned for the filter.... it's more of a 8-10whp depending on the tune, making it worth it.