I have an 05 I4 5 speed with a K&N intake. For the last several months I have been getting a P0171 every time my fuel gets down to about 1/4 tank. I put fuel in and drive a while and the CEL goes off. I've searched for solutions but can't seem to nail it down. No leaks with K&N, MAF cleaned, throttle body cleaned. Has anyone else had this problem.