p0171

My f 150 engine light recenty came on, so i got the code which turned out to be p0171. I also recently changed the plugs and the bank 1 side was running lean. furthermore, I have also gotten a k&n high flow air filter. could this be the problem, or should i get the injectors cleaned?
Jim

This is most likly an O2 sensor. replace them. I have an k&n filter on mine with no problems. You will need to clean your maf a week after installation to get ride of the oil build up on it. and when you clean the K&N don't put so much oil on it that it is driping. Clean maf a week after cleaning as well. K&N is worth it.