My 04 F-150 has always had a knocking sound wich they told me it was a lifter but I have never had problems with it. Just last week the engine started to loose power at some point while it was driving and when taking off I pressed on the gas to try to get it to go and the check engine came on I took it to get checked and it said knock sensor 1 and 2 malfunction. How can I know if the knock sensors are no good. Also do they need to have ground or can I move them from the block somewere else.

 

Post the actual pxxxx codes. I doubt both sensors would fail at the same time. I don't believe they are easy to get to either.

 

It's more likely the knocking sound is the VCT and the knock sensor failure is coincidental. If it's spark knock, it should go away with premium gas.

 

Will take it back to get checkd and ill post codes later.

Thanks