I recently installed a K&N air filter on my 2004 F250 Super Duty 5.4. A very short time after, my check engine light came on and I received a p0122 code, throttle/pedal position sensor A circuit low input. The truck is now running poorly and shifting somewhat hard. Any idea as to how to fix this? I am nearly 100% certain the installation of the k&n caused this. I would like to keep the K&N on if someone has a solution however considering going back to stock filter.

 

Hello gnther6 and welcome to FTE!

I doubt the filter caused your issue. I have been running a K&N filter on my 2007 5.4L since it was new, with no ill effects (despite what others will tell you).

Look inside your intake and at your MAF. Any dust or grunge getting past the filter? If not, the K&N filter is working OK.

It sounds to me like you just need to replace your throttle position sensor.

 

Thanks. It's puzzling to me. My truck ran awesome up to the point I stopped it in the garage, shut it off, installed the k&n and the problems immediatly started.

 

Also make sure nothing came unplugged when you replaced the filter.

 

Alright... call me a dumb a#* but I checked over the plugs and sure enough I did not reconnect the plug to that sensor. Plugged it in and all working fine now. Thanks for any replies on here.