Hey everyone, I've had a knocking noise coming from under the hood when idling and can't to exactly what is causing it. I took it to a mechanic and he said it was a bad idler pulley that was causing it. I had it replaced, but still hear the sound.

I'm no mechanic, but it sounds like its coming from the valve cover on the passenger side (used stethoscope to try and pinpoint it.) I recorded a video so you can hear what it sounds like.

Anyone know what it may be??

 

Sounds like the injectors. # Miles on the car?

 

It has 118k Miles on it. Model is a 2007 Base Coupe.

 

Suggestion: Let the car sit overnight. Remove the primary belt. Start the car. Are the sounds the same? I hear two different sounds. One sounds like the injectors. The other I can't tell. With over 100k-miles the injector sound is to be expected. DO NOT let the engine run for more than a few minutes without the belt, maybe 5-10 minutes. There is no coolant circulating without the belt. If the "knock" you say you hear is gone with the belt off this helps narrow down the source of the sound.