When my car is at idle, I hear the knocking sound. I have about 45,000 km about 30,000 miles. What causes knocking exactly? I've been putting the 91 octane gasoline for all the fill-ups and I still have the knocking noise? Can this problem be solved under warranty? or is this knocking normal?
Any input is appriciated.

 

Have you checked your oil level ?

 

Is it a 6 speed? If so, press the clutch in and see if the noise goes away. If so it is probably normal transmission noise.

 

Knocking at idle is not a fuel issue. Does it do it only when cold and then goes away after warm up or is it continuous? Either way, it's not normal and you should have it checked ASAP while you still have warrantee. Make sure they do an oil pressure check and be sure that you didnt use or admit to using anything but 5W/30 oil and a properly cross-referenced oil filter # to OEM.

 

I have automatic, so does that mean if I put in neutral, the sound should go away? I hear this knocking noise after the engine is warmed-up.

I should just call in the dealer and say I hear knocking noise? and I like to get it fixed?
What will be the future problems associated with this knocking noise?
I've never used any other kind of oil but 5w-30. Thanks for the help btw