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Can someone explain "faulty crankcase breather hose system" to me?

Old 02-06-2007, 04:09 PM
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RMN
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Default Can someone explain "faulty crankcase breather hose system" to me?

I had this problem last year and now, I'm assuming, again this year. The problem manifests itself as (very intermittent) loss of full power (almost always when stopped). That's not to say that all power is gone, but rather that only a limited amount of power is there when I put my foot down. Backing off and then putting my foot back down usually results in normal operation.

I understand the very basics of the crankcase breather system (i.e. why it exists: <a href="http://en.wikipedia.org/wiki/Crankcase#Air_ventilation">wiki</a>) but I guess I don't understand well enough to see how a problem could result in these symptoms.

Are we possibly talking about a blockage here?

Last year I got this fixed under warranty but I don't know if I'll have to pay for it this year. Any ideas on how much this will cost?

Big TIA.
Old 02-06-2007, 05:48 PM
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Default Doubtful it's your problem.....

When it's blocked/frozen it pressurizes your crankcase and blows your turbo seals; filling your exhaust (smoke screen) and intake with oil. You can't miss it when it plugs.

It's possible it could "malfuntion" and allow too much oil into your intake and cause your symptoms but usually they plug and pressurize the crank and then oil goes everywhere.

I can't recall ever seeing your symptoms caused by the breather though. Sounds like an ignition problem too me...you running cold plugs??
Old 02-06-2007, 06:09 PM
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Default hmm... well, here's the tech's writeup from last year

CAUSE: FAILED HOSE RRK
REPLACED BREATHER HOSE

TEST DROVE VEHICLE AND VERIFIED THE COMPLAINT. INSPECTED THE ENGINE BREATHER SYSTEM AND FOUND FAULTY CRANKCASE BREATHER HOSE SYSTEM. REMOVED AIR FILTER BOX, TURBO BI PIPE, SECONDARY AIR PUMP AND HOSES. REPLACED THE BREATHER SYSTEM AND INSTALLED ALL PARTS. TEST DROVE AFTER AND VERIFIED THE REPAIRS.

Both last time and this time, I pulled the following code (I even got a CEL a couple weeks ago after it happened once, but it went away):

16825 - EVAP Emission Control Sys: Incorrect Flow
P0441 - 35-10 - - - Intermittent

Several people made different suggestions... but after I took it in and they did the above, I didn't experience the problem for a full 10 months. I was also unable to link it with any environmental factors (like temperature) or even driving style (like it only happening when I've been driving hard... usually, that's when it happens, but I have noticed it once or twice when just driving normally).
Old 02-06-2007, 06:13 PM
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Default Uhhh? The EVAP system has nothing to do with the crankcase breather...

...system. That code would have been helpful in the first post.

Check your EVAP purge valve, probably leaking past it.
Old 02-06-2007, 06:16 PM
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Default so I'm still confused as to how the above fix stopped my problem

I know that the solution to that code relates to the N80 evap purge valve... but I still don't understand how it relates to my original question
Old 02-06-2007, 06:21 PM
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Apperantly it didn't.....
Old 02-06-2007, 06:22 PM
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Default sure, that's possible. I just found it surprisingly coincidental

plus, maybe I'm naive, but I figured they would have taken that into consideration

but maybe a huge oversight just explains it all
Old 02-06-2007, 06:28 PM
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Default :-)

Crankcase breather doesn't explain your symptoms at all. The EVAP system fits them really well.

I'm guessing you'll hear it's the purge valve this time which should last longer than 10 months.
Old 02-06-2007, 06:43 PM
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Default well, that's good to hear, I suppose

I read up on the valve in the past but maybe I don't have it quite straight... how could a stuck purge valve (either open or closed) cause this sort of behavior? The way I thought thing worked, the valve was just a way to purge fuel vapor from the gas tank / charcoal.
Old 02-07-2007, 03:18 AM
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Default

the EVAP system and PCV system are interconnected via the F-hose on earlier cars

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