What's causing this sound?

Also, there's a vacuum sound coming from my oil cap.


I've attached video footage below...
[media]https://youtu.be/Qcs618gsOZ4[/media]

 

Vacuum leak, somewhere?

 

Sounds like you spun a bearing.

Check the oil, both sides of the stick.

 

I'm with Billman here; you've got knock, that could likely be repaired if operation is ceased immediately...

 

Definitely Vacuum Leak, I remember having the CEL code for that.
I'll post the exact code, when I get home from work.


I rebuilt the motor, installed and properly measured all new bearings...I guess it didn't work?!?!? Sheesh.

 

Rebuilding this engine is only accomplished successfully by a very select few. It's very intricate and the slightest miscalculation ruins the resulting operation. Sucks, but sadly true...

 

I can feel and hear a lot of air pressure coming out of the oil cap, what causes this?
Best way to describe it is exhaust coming out of the valve cover.

I had a similar problem with my Prelude H22A motor, could this be attributed to oil ring failure, I can't think of what causes this....any ideas...


Also, how do you test which piston is causing the rod knock?

 

You'll likely find out on by looking at the wear on the crankshaft or the bearings. If you have gold flakes in your oil... you'll know upon disassembly.

 

Good god that sounds bad!

 

You rebuilt this engine? Does the sound go away when you touch the throttle? Or is it always knocking? Hopefully it's a rod knock and not the mains, that can be fixed without tearing the engine apart. If the sound goes away when you increase revs then I'd say it's valves, but if it's persistent and changes with rpm it's crank or rod bearing related. As for your air pressure coming out of the crank case, you're either getting horrible blow-by or your PCV isn't up to snuff. That crankcase pressure will go out the path of least resistance, usually it's your dip stick, but it can also be the rear main seal.