Honda D Series Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
So I yesterday I changed my PCV valve on my Civic EK3 (D15Z6) because my engine was consuming a lot of oil and I also noticed some smoke and I thought it would be the PCV valve that was blocked and the air was comming out by the Crankcase Breather Hose with some oil.

After changing the PCV valve I checked again the Breather Hose and it still blows some air out to the intake with a little of oil.

What should I do to fix it, because the Breather Hose is supposed to suck air into it and it's doing the opposite (blowing air to the intake).
 

·
\/Your Mom Was Here\/
Vibe GT
Joined
·
4,833 Posts
It should be sucking air into the intake through that breather hose, the valve makes sure it's only one way. It sounds like you got a blow by from the piston rings, has the engine ever been overheated or run hot?
 

·
Registered
Joined
·
9 Posts
Discussion Starter #3
Well it overheated once because the fan fuse blew and the fan didn't work but I don't think it was enough to cause engine damage (not sure tho)

I can't post images because I haven't posted enough posts so i'll leave a link with a picture.

i.imgur.com/0j1TF8p.jpg
 

·
Registered
Joined
·
9 Posts
Discussion Starter #5
Shouldn't the air be sucked by that hose into the crankcase and exit via PCV valve hose to the intake, isn't that how it should work? That's why some people put those little air filters I guess, but then again, I'm not an engineer and I only know the basic about how engines work.

Is it normal air coming out of the Breather Hose with (a little) oil?
 

·
Meat Popsicle
91 CRX Si
Joined
·
2,936 Posts
The PCV system is completely stock with the cylinder head cover plumbed to the intake and the block breather/PCV is connected to the intake manifold?
 

·
Registered
ej8
Joined
·
6,365 Posts
The way it works is the pcv suck the blowby out the crank case.
The nipple on the valve cover is an inlet for fresh air.
If you look at the oem setup. There is a slash cut in the tube. This slash lets the in coming air be push into the valve cover.

Most people upgrade there tube and it doesnt have this slash on it.

So to recap.
The nipple on the valve cover is an inlet not an outlet.

If you have a ton of press coming from that hose then you have some blowby.
ideally that port should be free of oil and have very little to no pressure on it.

Might wanna clean or get a new pcv hose.
If its still alot then its just to much blow by
 

·
Registered
Joined
·
9 Posts
Discussion Starter #9
The way it works is the pcv suck the blowby out the crank case.
The nipple on the valve cover is an inlet for fresh air.
If you look at the oem setup. There is a slash cut in the tube. This slash lets the in coming air be push into the valve cover.

Most people upgrade there tube and it doesnt have this slash on it.

So to recap.
The nipple on the valve cover is an inlet not an outlet.

If you have a ton of press coming from that hose then you have some blowby.
ideally that port should be free of oil and have very little to no pressure on it.

Might wanna clean or get a new pcv hose.
If its still alot then its just to much blow by
Exactly that's what I said that "nipple" on the valve cover is for air entry! But mine is blowing air out, I thought that by changing the PCV valve it would work correctly but it still blowing air out by that breather!! Where might be the problem? Headgasket? or PCV valve HOSE blocked? (because the valve itself is brand new)
 

·
Registered
Joined
·
9 Posts
Discussion Starter #10
nipple is for air exit and the fumes get sucked in through the throttle body. Why putting a filter on there is stupid.
like xile6 said, it's a air inlet and not outlet, because it would be stupid to have 2 air outlets...

It's part of the Positive Crankcase Ventilation, air enters by that crankcase breather (that's why people put air filters there), and then exits by the PCV Valve Hose to the intake to be burnt in the cylinder to reduce the emissions to atmosphere.

My problem is that the breather is blowing air instead of sucking, I may have the PCV Valve blocked?
 

·
Registered
Joined
·
9 Posts
Discussion Starter #12
Okay, so I've fixed the problem, the PCV valve hose was blocked and air couldn't pass through it.
Now the PCV system is working how it should

Air enters by the Crankcase Breather and exits through the PCV Valve hose to be burned in the combustion, the oil consumption should now reduce (I hope :D)
 

·
DIY Guru
96 Ranger-stock
Joined
·
637 Posts
Unless you gooped up the oil drain back holes in the pistons behind the oil scraper rings

or

when over heated you lost the tension in the rings


But a leak down test will let you know if you cooked the compression rings , but not if the oil drain holes are clogged
 

·
Registered
Joined
·
9 Posts
Discussion Starter #14
Okay so it has been a month after fixing the pcv valve problem and the oil change.
Before fixing the problem, doing 200km would reduce the oil level a lot and I've done 600-700km and the oil still on max level and I can't see any smoke coming from the exhaust anymore.

I also noticed a few months ago when I changed my exhaust muffler was small "black" dots on the rear of the car, what could it be? Fuel?
 

·
Registered
Joined
·
9 Posts
Discussion Starter #16
Unburnt fuel...

If you just route the line to a catch can it won't suck oil into the engine.

It's a bit annoying having to clean the rear everytime because of those "black dots" of fuel :?:?:? is there any way to avoid that? :jerkit:

When I was searching for a fix for that Oil/PCV problem I thought about the catch can but I don't think there's a need to do that now that the problem is fixed :cool::cool:
 

·
Registered
92 cx
Joined
·
934 Posts
You could make some kind of shroud that goes around the muffler exit to block the gases from going up onto the bumper and bolt it to the bumper. Or get rid of your aftermarket exhaust and put a cat on it.
 

·
Registered
ej8
Joined
·
6,365 Posts
Wax your rear bumper and it will wipe off.

But the reason your getting it is because your running rich.
Normally it happens when you add a header and intake to civics.
Had this happen to my del sol long time ago. Was 90k on the motor.
 

·
Registered
Prelude, Integra DB9
Joined
·
373 Posts
But the reason your getting it is because your running rich.
I agree, even though my experience with Ds is limited.

If the car feels like it's running properly, there's nothing too serious happening. Except that the tune's not right for part of the rev range. I wonder if you've perhaps done enough mods to confuse the ECU?
 
1 - 19 of 19 Posts
Top