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My car has no PCV valve?!?

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Old 12-04-03, 06:52 PM
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Unhappy My car has no PCV valve?!?

My mechanic and I (JPR Iports in south jersey. I would recomend Jim to anybody) have been investigating the many oil leaks my car seams to have for two weeks now (three times). The oil seams to be leaking out of every seal that it can (4 or 5 very noticable places -- metering pump seal, turbo seals, IC couplers, all over the engine block, etc...). He steamed cleaned the engine and after a few days it's just as bad as ever, but we couldn't find specifically what was leaking.

So tonight we notice that the car has no PCV valve and that the nipple coming off of the oil fill stem is just capped off! This seams to be very bad to me b/c it has been like this since before I got the car which was 10k miles ago. So I've been driving it (hard) like this for a year straight as daily driver.

Could this cause any long term damage to my motor and tubos and maybe anything else? Thanks.

-Matt
Old 12-04-03, 06:57 PM
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95's do not have a PCV valve.
Old 12-04-03, 07:00 PM
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Originally posted by Zyon13B
95's do not have a PCV valve.
I thought 95's don't have an EGR valve, but that they have a PCV valve..
Old 12-04-03, 07:03 PM
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95s don't have an EGR but certainly have a PCV. However, the PCV is not plugged back into the intake tract like it is with 93-94s. Therefore, we 95s don't have quite the track leakage that 93-94s do....
Old 12-04-03, 07:05 PM
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Originally posted by rynberg
95s don't have an EGR but certainly have a PCV. However, the PCV is not plugged back into the intake tract like it is with 93-94s. Therefore, we 95s don't have quite the track leakage that 93-94s do....
rynberg, could you please explain this more for a PCV noobe like myself .
Old 12-04-03, 07:14 PM
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Originally posted by Zyon13B
95's do not have a PCV valve.
I guess I need to add "vented to filler neck"

NEways you could try a catch of some sort in the line returning to the intake, it should eliminate some excess oil.
Old 12-05-03, 09:50 AM
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Originally posted by Zyon13B
I guess I need to add "vented to filler neck"

NEways you could try a catch of some sort in the line returning to the intake, it should eliminate some excess oil.
so where is the PCV valve in a 95?
Old 12-05-03, 10:10 AM
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My car (a '93, but I assume this changed when Pettit rebuilt my motor a few years ago) doesn't have anything attached to the filler neck either. I've been told its normal, and I certainly don't have oil leaking all over the place.

jds
Old 12-05-03, 12:31 PM
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Early FDs have two ways to vent exhaust/other fumes
from the pan(crankcase) into the engine for burning.
A traditional PCV valve between the oil filler neck and UIM, and a hose going from the oil filler neck to the #1 turbo inlet.

The PCV valve is a possible source of failure. If stuck open, under boost you will pressurize the crankcase.
This has happened . Since the other hose does the same thing, many of us have removed and blocked off the PCV circuit. Same thing is done by many road racers as they must have an oil catch can.
Old 12-05-03, 12:55 PM
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currently im running the hose to the turbo intake elbow and have the pcv blocked off. but i think i am about to reverse this. my reasoning is if im going to be sucking up oil i would rather have it go through as little of the intake as possible. the pcv goes straight to the manifold instead of going through the turbo and intercooler first. what do people think about that?
Old 12-05-03, 02:00 PM
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Originally posted by rockshox
currently im running the hose to the turbo intake elbow and have the pcv blocked off. but i think i am about to reverse this. my reasoning is if im going to be sucking up oil i would rather have it go through as little of the intake as possible. the pcv goes straight to the manifold instead of going through the turbo and intercooler first. what do people think about that?
Under boost you will have no way of venting crankcae pressure since the pcv is closed under boost. The only place there is vacuum 100% of the time is at the turbo intake.
Old 12-05-03, 02:02 PM
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right but now long are you under boost continously? i cant see that this matters.
Old 12-05-03, 02:36 PM
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Originally posted by rockshox
right but now long are you under boost continously?
The car is on boost nearly 100% of the time if you do any amount of road racing at all.
Old 12-05-03, 03:45 PM
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i do a fair amount of road racing and usually i brake before every corner.
Old 12-05-03, 06:53 PM
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any more opinions? i obviously know the pcv isnt active under boost but there is still enough time to relieve pressure.
Old 12-05-03, 09:17 PM
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well if you are pressurizing the crankcase, any seal that is about to go will go...

The best is to vent it into the air thru oil catch can.

I am thinking of eliminating the charcoal canister vent too..
Old 12-06-03, 08:08 AM
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Originally posted by rockshox
i do a fair amount of road racing and usually i brake before every corner.
Good point Every corner? See how many consecutive seconds you stay on boost next time you're out; I bet you'd be suprised. Also keep in mind the engine is at high RPM, so that time spent on boost with no crankcase venting is not the way to go IMO. Once you make any seal or gasket begin to leak, it's just going to keep leaking.
Old 12-06-03, 12:08 PM
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I'm still confused... how or where does a 95 relieve crankcase pressure?
Old 12-07-03, 01:35 PM
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search robinette site under pcv valve. your answer is there with a diagram
Old 12-07-03, 02:10 PM
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moehler, my car is at JPR w/ jim as well (broken clutch fork) does ur car have a 99 spec front end unpainted? alittle off topic, sorry
Old 12-07-03, 03:30 PM
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Originally posted by jfxp
moehler, my car is at JPR w/ jim as well (broken clutch fork) does ur car have a 99 spec front end unpainted? alittle off topic, sorry
nope... it's white and has a stock exterior. I have it at home now.


Originally posted by R. Gambino
search robinette site under pcv valve. your answer is there with a diagram
Thank You!! The diagram and expalination is here:

http://www.rx7turboturbo.com/robrobinette/pcv.htm

From this, it seams that the 95's should have a tube coming off of the filler neck and going to the turbo inlet path. Am I reading this correct?
My car just has the nipple on the filler neck capped off?!? So I should still look at this as source of concern, right??

Old 12-07-03, 05:16 PM
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bad idea

Originally posted by rockshox
currently im running the hose to the turbo intake elbow and have the pcv blocked off. but i think i am about to reverse this. my reasoning is if im going to be sucking up oil i would rather have it go through as little of the intake as possible. the pcv goes straight to the manifold instead of going through the turbo and intercooler first. what do people think about that?
the pcv valve is designed to only permit a small amount of flow to uim at idle, high vac. a large line would likely result in uncontrolled idle.

ok to lose the pcv, but the vent tube from filler neck to tubo inlet should always be used. for track use, i use an ast-like closed catch can, and drain it ocassionally.
Old 12-07-03, 05:48 PM
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Anyone got a pic of this valve? I think mine may be leaking too, just want to positively confirm the identity of this part
Old 12-07-03, 05:53 PM
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Originally posted by SanJoRX7
Anyone got a pic of this valve? I think mine may be leaking too, just want to positively confirm the identity of this part
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