Hello everyone! I am new to this forum, but I already have a problem on my hands with my '06 Focus ZX5 2.0. I deleted the factory maintenance free air box and instead installed a K&N filter from their part number 57-0595. Really all I did was remove the air box and use a 3 inch piece of pipe to connect to the throttle body hose the new filter. I drove it right after and it ran great! Then after I turned it off for a bit, came back out and went for a second drive, the check engine light came on and gave me a P0102, low MAF voltage. I have no idea what to do from here, as I checked all the connections and they seem good, with one exception:
On the bottom of the filterless box assembly, near the push button filter life reset thing, there was a barbed fitting molded in that looked like a vacuum hose should have gone there, and I never found that hose to reconnect after the air filter install. Does anyone know if there is supposed to be a vacuum line running to the bottom of that air filter box? Here is a top view picture of the box before I yanked it out:
If not, I am more puzzled, and my Focus is stalling at low speeds when I have the AC on and make turns into parking spots, and seems to surge at times. Overall though, once moving, it runs well.
Any help on this would be greatly appreciated, I have owned this car since I bought it new from the dealership and this is the very first time the Check Engine light has ever come on!
Thanks!!!
-Randall
On the bottom of the filterless box assembly, near the push button filter life reset thing, there was a barbed fitting molded in that looked like a vacuum hose should have gone there, and I never found that hose to reconnect after the air filter install. Does anyone know if there is supposed to be a vacuum line running to the bottom of that air filter box? Here is a top view picture of the box before I yanked it out:

If not, I am more puzzled, and my Focus is stalling at low speeds when I have the AC on and make turns into parking spots, and seems to surge at times. Overall though, once moving, it runs well.
Any help on this would be greatly appreciated, I have owned this car since I bought it new from the dealership and this is the very first time the Check Engine light has ever come on!
Thanks!!!
-Randall