i was messing around on ebay and ran into a module that claims better fuel mileage, heres link http://cgi.ebay.com/ebaymotors/SAVE-...spagenameZWDVW and i know k and n are good filter, got one in my chevy truck but does it help out mileage on the hhr, at 3.00 bucks a gallon i gotta try to get all i can.

 

Save you're money!