I took the valve cover off. All of my intake valves were at .006". I think the shop I took it to may have adjusted them all too tight. I don't think that's the cause of the knock, though.

I noticed I can wiggle my timing chain. I can pull it up a hair, maybe less than 1mm at the top of the gear. When I rotate the motor forward and backward, you can see the slack build on either side. I have another motor in my garage, (spun bearing), that has 35k miles on it. I can't move the chain at all. I don't see any slack when I rotate the motor. I know there's no oil pressure in both motors, being that they're off, but I'm seeing different results with the same test.

 

Sounds like that might be a good place to check out. My chain also does that.at the very top it has a very slight movement. But since I don't have access to another motor to check out I thought that was normal.i don't know whether the chain has to be super tight with no slack at all.

 

I think that sound comes from the chain as well, not sure why it is less when you pull the #1 coil, but I bet this would actually help further diagnos it. I have had this on every chain driven Honda I have owned, although not as loud as yours. To me, on my car, it sounds like noise directly from the chain. I really wish the experts would chime in on possible causes.

 

I have never worked on these motors. Only b series. I checked the price for a timing chain kit and it's like 650 bucks.

 

Check the play vs service manual. I think ballade sells a bigger cam chain sprocket but idk if it would fix your issue.

 

Pulled the pan and inspected cyl 1. Not a worn bearing, no play at all. No side to side play either. I don't see any scoring in the cylinder. I'm at a loss. Checked valve lash on top, and bearing condition on the bottom.. there's no reason this noise should exist. The car burns almost no oil, there's no shavings, and it still has power.

Maybe worn valve guides? Perhaps a valve is banging around until it expands enough from heat? Retainers were swapped to AP2 a few days before the oil change.

 

Wouldn't likely be the valves, maybe it's one of the accessories, have you tried running the car without the serpentine belt for like 30 seconds? Have you tried also setting perfect TDC on the valvetrain and seen if it lines up the timing marks for the crankshaft? This would tell you if you have a stretched timing chain.

 

I think it has something to do with the timing chain. Because u said it had a small amount of play on top. My car has exact same noise with exact same play on the top. And it happened after u did an oil change just like me.im thinking the chain stretched.

 

I have run the engine without the belt, still makes the noise. I'll take a closer look at the timing.


Just doesn't explain why the knock goes away when I disable the cylinder.

 

Unless it coincides with the position of the chain and stroke of cylinder 1, somehow causing the chain to rattle/slap