Hi all, I just noticed something that now that is hot was a bit easier to pinpoint. I say pinpoint but am looking for the group wisdom. I hear a knocking sound that diminishes when the AC is turned on. I think it is louder with it off though. Facing the engine I hear it coming from the right side of the engine. Could it be my air compressor failing? My car MY10 LR4 has had the timing guides, chain tensioner replaced. I am sure that is not where the sound is generated. Thank in advance for your insight.