K&N Air Filter
Member
Joined: 09-11-2007
Posts: 43
From: Alabama
I have a 2006, 2LT with the 2.4 and automatic trans. The only changes made is addition of Amsoil Synthetic oil and the use of some Berryman fuel additive on an occasional basis. The car had 26K showing when I bought it used. I am a long distance commuter driving 78 miles one way to work. This HHR has given me a pretty consistent 30 mpg or MORE since I put it on the highway in July of 2007. The best number I have gotten was about 33 mpg when the entire tank was expressway driving. As mentioned, I have changed NOTHING except the oil and fuel additive. I recently got rid of the FireHawks and replaced them with BFG Traction T/A in 215X50X17. These made a huge driveabiltiy difference, but no change in mileage. The car has 55K on it now and still delivering excellent mileage. I have noted the newer engines take a while to "loosen up" and that may be the issue for some drivers with newer cars.
Member
Joined: 03-25-2008
Posts: 91
From: SW Florida
I have an 07 2LT auto that now has 33k miles. I drive 108 miles roundtrip for work. It is a mix city/hwy. I get an average of 25.7-26.1 city, and 27-28 hwy. My hwy driving is 75-80 mph for a couple miles then 55-65 for a few miles. One time I was able to cruise the whole way at 80mph and got 29.8 mpg.
Senior Member
Joined: 05-26-2007
Posts: 1,554
From: ...
The K&N filters... actually any oiled cotton gauze filter... also gives you the unseen added bonus of micro oil film on your MAF's thermistors. 
Only dry paper filters for me. I like the MAF's on my cars to stay clean, dry, and calibrated.
Only dry paper filters for me. I like the MAF's on my cars to stay clean, dry, and calibrated.
Member
Joined: 05-18-2010
Posts: 58
From: Michigan
I have owned about 10 cars in my life and ive ran a K&N in most all of them. No performance difference , no oil on any sensors, no dirt on the wrong side of the filter, I did however save alot of dollars on expensive filters over the years. Interestingly though this HHR reccomends a change in normal driving only every 50,000 miles. May stay stock filter on HHR.
Senior Member
Joined: 03-09-2008
Posts: 725
From: Elko Nevada
I put a K&N filter in and it threw codes and reduced engine power every time I got on the gas. I have since put a regular filter back in and no problems since. The 2 times Ive ran K&N Ive had problems, so its normal filters for me from now on.
Senior Member
Joined: 07-17-2006
Posts: 6,053
From: Dallas, GA
I have owned about 10 cars in my life and ive ran a K&N in most all of them. No performance difference , no oil on any sensors, no dirt on the wrong side of the filter, I did however save alot of dollars on expensive filters over the years. Interestingly though this HHR reccomends a change in normal driving only every 50,000 miles. May stay stock filter on HHR.
