2005 v6 engine knock when accelerating

[SeaPro]

The engine sounds excellent, but frequently when Im driving between 50 -60 kilometers per hour, I'll hear a bit of knock when I press on the accelerator. If I increase speed past 70 the knock goes away. It's like a quick pre-ignition knock that happens as soon as I accelerate. If I tap the gas quickly when doing around 50 - 60 I'll hear it every time, regardless of terrain.

I always use Premium gas (92 is the best I can get here). I change the oil and filter frequently (just did it after about 3000km to see if that could be related) with 5W20 synthetic.

I know it's difficult to diagnose a problem without hearing it, but I was hoping someone could give me some possibilities of what could be causing the knock.

In the spring I'm going to pull of the air intake and change all coils / spark plugs, but what else could potentially cause this problem?

Thank you.

 

[don-ohio]

Check that the drive belt tensioner isn't hitting its stop.Sometimes they knock,but usually on start-up. don-ohio ^)

 

[joegr]

Are you sure it's not pinging? (knock = really bad, pinging = probably okay)
It sounds like you are describing pinging. A little pinging under mild acceleration can be normal.