DIY: Make an aftermaket PCV into an OEM VX PCV

[TomO]

This is a DIY that is meant for the VX crowd that doesn't have the OEM PCV "Elbow" and want theirs to be like the stock one again. Honda doesn't sell the OEM one anymore.

A little background:
The OEM PCV (Positive Crank Vent/Valve) is no more than an emissions elbow with no internals inside it. Most of the previous owners of the VX have had theirs replaced and since the VX is such an odd car, the replacement part is actually a normal PCV. The usual test to see if a PCV is good is to remove it from the car and give it a shake. If it makes a clicking noise, it's still good. If it makes no noise, it's bad. Since the OEM one has no internals, it makes no noise and the mechanic/person will replace it.

On to the DIY:

Things you need:

• PCV (I'm using the "blue" aftermarket replacement one from Fram)
• Sharp utility knife or hacksaw
• About ten minutes of time

So you have your PCV


You'll want to secure your PCV and start cutting just above the tip. If you look inside the small hole on the PCV you'll see the plastic tip is about an 1/8th of an inch thick. Cut right where you see the saw placed in the picture you'll cut just above that thick part and things will work out great.


Once you've cut off the tip, it should look like this


Now gently turn the PCV so the black part is pointing down and the plunger and first spring will slide out like so


There is one more spring to get out of the PCV, it is the small one in the picture. You should be able to tap the PCV a few times with the black end pointing down and the small spring should pop out.


The PCV should now be free of all internals


Now you can clean off any strands and debris from the modified PCV.

Install the modified PCV back into the car and enjoy the sense of accomplishment.

Theory:
I believe the reason that Honda set up the PCV system on the VX like this was to run a higher vacuum on the lower end of the motor. This helps to combat pumping loses in lower RPMs.

If you have any questions or comments, feel free to post them here.

keywords:
d15z1 PCV positive crank vent valve VX emissions hose Civic Honda d-series d15 VTEC VTEC-E idle blue Fram DIY how-to how to mpg FE modify

[SVOboy]

SRW is going to have some stuff to add to the DIY directory,

[TomO]

Yes he is. You are welcome to swipe this for your site as well.

I also will PM you later today when I have a running tally of what I need for server space, if that offer is still good.

[trebuchet03]

Hrmmm.... So what do you think will happen if this is done to a non VX?

It would seem that more vacuum will make less losses in one direction... But more in the other... Basically, even. Just like engine off coasting with an open throttle vs. closed... Then again, it's subsonic (I would hope so ) with a much larger volume and not exactly sealed...

[Silveredwings]

Originally Posted by SVOboy

SRW is going to have some stuff to add to the DIY directory,

Done. Nice write up.

[TomO]

Originally Posted by trebuchet03

Hrmmm.... So what do you think will happen if this is done to a non VX?

Nascar runs high vacuum on all their engines claiming it helps with efficiency.
On a non VX Honda, the IACV should be able to compensate. One car still run a traditional PCV in a Non VX as well and be fine.

Originally Posted by trebuchet03

It would seem that more vacuum will make less losses in one direction... But more in the other... Basically, even. Just like engine off coasting with an open throttle vs. closed... Then again, it's subsonic (I would hope so ) with a much larger volume and not exactly sealed...

True about the one way help. But I see the Higher Vacuum helping to clear the blowby vapors from the crankcase. Plus it isn't technically a vacuum (that would make the motor implode as well as the car, lol) but a lower than atmosphere pressure zone. And there is the fact that the sealing isn't the greatest on the system as well.

[LarryClapp]

That actually explains for rough running after replacements like that. Putting an Aftermarket in,I would bet the MAP Sensor would send some pretty crazy signals, along with the O2 Sensor to ECM for which it would have to compensate for. I would bet it probably is running SUPER LEAN!