hondan00b95

My PCV valve seems to be pulling oil into my intake manifold. Unless there is some other way for oil to end up there... Out of the 4 people I have asked, 3 said "Nah, that's fine." The more I think about it, the more I'm pretty sure they are wrong. I assume oil in the IM is a no-no. Could result in burning oil? I am burning oil, but assumed it was rings or valve seals. Could result in jacked up sensors? Mine have been all frigged up!
So, my question, is the PCV line from VC to IM nessecary? Last night I decided to try to plug the IM side and leave the VC/PCV open for pressure release. Is this okay? In my research I also found something about dump boxes or oil collectors?

95 civic coupe, b20z, blox intake mani.

Former User

*PCV

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hondan00b95

Thank you!

speedjunkie_g35

Hook it back up and leave it. You can potentially damage your motor. Those 3 people you asked were correct.

hondan00b95

More info would be helpful.

TomCat39

A little bit of oil will pass through the PCV valve into your intake. It's why swapping out the valve every couple of years is a good idea. The breather box doesn't separate all the oil from the gasses. This is perfectly normal.

Your unhook job basically mimics the design of pre-emissions. The crank case used to be vented to atmosphere. You are basically just making your car fit into the gross pollutant category.

The better modification would be to add an oil catch can after the breather before the pcv if you are concerned about it.

The amount of oil passing through the pcv system is minimal. If it wasn't, your spark plug the pcv system runs to would foul all the time but from my experience it looks clean and soot free until valve seals go.

Find which runner your pcv plugs into and compare that plug to all the others, you should find it is just a touch darker in tan color than the others but still soot free and tan. A.K.A. it's perfectly fine and not harming a thing.

Your burning oil is most likely valve seal related or ring related or both.

hondan00b95

Thanks so much, now I have somewhere to start!

hondan00b95

Update: I put the line from PCV to IM back on this morning. A couple of hours ago I was working on an idle issue and had two engine codes thrown. IACV and IAT. Upon replacing the IAT, I realized it was soaked in oil. I decided to check plugs like you said and the one connected to the PCV runner was also drenched in oil. So it is pulling far too much oil therefore I am getting a new PCV tomorrow. Any other things to check/be aware of?

shotoutacc0rd

Use a GOOD pcv valve, not the cheapo ones from pep boys or something.

TomCat39

To isolate the PCV valve, I'd swap in a new PCV and monitor, if it starts to foul the plug, I'd pull the connector tube and plug the IM like you did and vent the crankcase to atmosphere for a bit and monitor again with a new plug.

If the plug doesn't foul at this point but did with the pcv system hooked up with a new plug, then you know it's the pcv system. Not likely but that is the way to rule it out.

At that point I'd spend the 100 bucks for an aluminum catch can that I could throw a stainless steel pot scrubber into and call it a day with monitoring to be sure.

It is probable that your pcv valve is stuck open and is sucking at all times not just when crank case pressure is positive.

hondan00b95

Alright... I saw a couple catch cans on some threads here, so I will look into that. Will update within the next couple days. Thanks for all the help!

TomCat39

As you wish. I think it's a bit premature to drop cash on a catch can but it's your call.

Another detail.... You have a B20Z you say... Is the PCV valve original (for the 95 coupe motor Z6 or B7 or Z1 or B8)? Or did you get the PCV Valve for the B20Z?

Every PCV Valve is calibrated for each motor being the vacuum and crankcase pressures are different etc.

hondan00b95

I honestly do not know the answer to that

tony_2018

Could at least buy a replacement pcv from Honda before getting the oil catch can.

hondan00b95

I just grabbed a PCV from autozone for a few bucks. Ran it for a couple days. The IAT, has no oil on it now... I still have to check the spark plug though. The IACV and IAT do not seem to be giving me problems anymore... The car is still running rough but I assume it's not related to this.

Autozone just had a pretty general PCV valve for most b series, so maybe I should grab another more specific one from honda?

shotoutacc0rd

I would wait until that one fails in like 5-10k miles. But, on the other hand, also IV read that different b series engines do have different valves

94eg!

iTrader: (2)

Not only is the PCV valve a valve, it's also a specifically sized restriction to keep the manifold vacuum from pulling too much or too little crank case air.

h-thomforde

I have a 97 Civic CX with 270,000 miles. After being parked 6 weeks it hicups at low idle. I am in the process of checking PCV valve and vacuum hoses. I've never changed the PCV valve because I've never been able to locate it. I read on Wikipedia that all 1997 Civic CX have a D16Y7 engine. I've peered and felt around and can't find it on the intake manifold below the fuel injector rail, and I can't find it on the valve cover. Any suggestions? How can I get a better look? What hose to I follow to feel it?

grumblemarc

iTrader: (4)

Troll post. If not Google for the Field Service Manual and download it. It has pictures and everything.

94eg!

iTrader: (2)

The 97 CX has the PCV (#3) plugged directly into the oil separator (#1). It's not on the intake manifold, it's underneath it.

h-thomforde

I have a 1997 Civic CX with 270,000 miles. After being parked 6 weeks it hicups after warm-up while idling. I swoped vacuum hoses without effect. Next I want to check the PCV valve. I've never changed the PCV valve because I can't locate it. I think I have a D16Y7 engine. I read on Wikipedia that all 1997 Civic CX models have a D16Y7 engine. The PCV valve is not on the valve cover. I've peered and felt around and can't find it on the intake manifold below the fuel injector rail, but I think it must be there somewhere. Any suggestions? How can I get a better look? What hose to I follow to feel it? Thinking ahead, I know it might be one of the oxygen sensors, but I've been driving the car with a faulty oxygen sensor for more than 50,000 miles, and the hicups at low idle only just began. Anyway, if its not the PCV valve what else should I check?

grumblemarc

iTrader: (4)

How many PCV valve threads do you need? Someone posted a picture of where you'd find it.

andoxviii

iTrader: (1)

http://www.hondaautomotiveparts.com/...28DOWN+FLOW%29

veks

x2 speaking of pcv valve I need to change mine.

TomCat39

Threads merged, one thread per car typically is how it goes.

There are exceptions but this doesn't look like one of them.