I have a 2007 Civic SI with 145k miles. (K20Z3) I noticed this ticking noise after the first time i adjusted the valves on it. So of course I figured it was the valves, but now they've been adjusted like 4 times by me and taking to a shop to do the vavles and timing chain. The noise is still there! Im not sure if this is normal or natural. I never ever noticed it when I first got the car and I'm usually very sensitive to engine noises so I don't know I broke something somehow when first doing the valves or what! Only think I can think of is either the valves or I know I replaced the PCV valve around the same time could it be that? I know people say the K20s are loud and have loud injectors and I have used injector cleaners so maybe that made the injectors louder? I feel like I would've noticed this noise before or something, but its possible I suppose. So is this noise normal or natural? I feel uncomfortable with how loud it is, although I'm quite certain its nothing catastrophic. The car is stock other then a K&N Cold air intake FYI.

 

That's does not sound like normal tick.
Is it louder/quieter when it's cold/warm?

 

I cant really hear the tick above 2k RPM so when I first start the car it sounds fine but once it’s below 2k RPM I can hear it and it’s the loudest and idle around 900 rpmish

 

My 09 Si sounded like this also. I changed the belt and I saw the belt as worn and I didn't hear that noise. And at times it may sounded like that whet I had the ac or heater on. But I don't hear it any more but at times when cold.

 

Hi man! Have you ever solved this ? What was it? Im having some similar sound.

 

I'd agree with the above poster, it's the belt or at least in that area. Belt, belt tensioner, etc...