Thomas Guide

Oh man, not sure if I should be taking advice from you then, staying in a hotel is risky business these days...could have gotten the Bat Flu or beaten up in a riot!

Mileage is 115,500 miles and am original owner, original/stock engine without any previous issues, and all maintenance and new parts added as needed (like coil packs, spark plugs, fuel injectors, rubber gaskets)

jyeung528

does the sound go away when you relieve crankcase pressure (removing the dipstick)?

Thomas Guide

Ok, here are some updates:

- There is no oil coming out of the PCV, the PCV hose running to the intake is free of oil and only dirty inside (I ran a long cotton swab into the PCV and the hose, also the connecting point on the intake)
- Removing the dipstick makes no difference to the noise

I recall seeing another test for blowby (video of the test explanation and my results below), where you remove the oil cap and perform the following tests:

- Is the air consistent? - Yes, mine is a steady consistent pulsing
- By placing the oil cap loosely on the opening does it move? - Yes, mine jumps around quite a bit
- If you pinch the PCV does it move even more? - No, I also flipped the cap on both sides and there was no change

I don't know what that test tells me lol. Anyone have experience with this or can they check theirs to compare to mine?

My Engine Blowby Oil Cap Test Results:

Engine Blowby Oil Cap Test Example:

flanders

What were the numbers on your last compression check?
Have you checked and cleaned the other large valve cover breather hose?

Thomas Guide

The other breather hose was replaced last year with OEM. But I checked it just now and there's no oil in it and just a bit of black soot or dirt, I gave it a few swipes with a cotton swab. (should there not be any soot in there?)

Here's the complete wet/dry compression and leakdown #'s before and after a valve adjustment.

jyeung528

well, it's not blowby causing the noise because you still have the noise when you remove the oil cap (or dipstick). the blowby should be venting out of the oil cap rather than the pcv.

at this point, i would try another brand new oem s2000 PCV.

jyeung528

you could also remove a pcv with hose from an s2000 that is not making that noise and swapping it onto your car. see if the noise switches to the other car, or maintains on your car.

that would be a great diagnostic move to pinpoint or exclude the pcv (and hose).

Thomas Guide

@jyeung528 Great observation on the blowby, so if I don'thave blowby, what would cause my dipstick to pop out and also have oil blasted all the way up the length of the tube (it never did this until all 3 symptoms started).

In the last 2 years I have replaced the PCV with two new ones so this would be the third new one in that time frame (total 4 including the original), it's cheap enough to do again so we'll see in a few days, but statistically would be odd that all three previous ones failed in some manner to make this noise. I don't think any of the previous ones failed either.

Slowcrash_101

You mentioned that you don't have the original valve cover, have you tried using a different one?

Thomas Guide

I actually do still have the original one, I've been hesitant to swap it out because of how badly it chipping and peeling and the mess that comes with it. The new one is an OEM one as well. But it has nagged me if there is some deviation in the new one causing this in some way.

Looks like I have another project here to strip the old and and swap them out and try...