Emmision light came on, had a friend read the code it said running lean.. I have a 04 5.4 with K&N intake and dual flowmaster stock cats... Should i get a tuner? is that all i should do or should i go to factory first? and Why did it take 6 months to give a lean code???

 

You do need to get a tuner from what I was told. As to why it took 6 months for the light to come on, it could be build up from the oil (from the K&N filter) onto the MAF sensor.

 

well took it to ford and they belive it to be a cold start issue b/c of the temp the reading stated the code happen and the long ft and the other one were way off and it stated on the print out it was at 8 mph .. so they will keep it till monday morning and do a smoke test to find the leak...