# Ok, pull dipstick, engine starts shaking, means bad PCV??



## jasejtw (Jul 19, 2007)

I've read a lot of topics about bad PCV valves (sry to start another one), and i have read several ways of checking to see if the pcv is bad. But one method i've read is while the engine is idling to pull the dipstick up enough to break the seal with the crankcase, and if the engine starts shaking that means the PCV is bad. Also I have read to crack to oil cap while running, basically tests the same thing. Well i tried the diptick momentarily today and sure enough it started shaking. So do this definitely indicate a bad pcv vavle? or am i misinformed about this method of testing? and why does it make the engine shake is the pcv is bad and you break vaccuum on the crankcase system. Basically how its works so i can explain to the dealership the reason why this means my pcv vavle is bad. Im a logic way. Any input is appreciated.


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## bwzimmerman (Jun 16, 2007)

that doesnt sound right.. but i am not a mechanic. I do know that it means a lost of vacuum or engine pressure. I installed a noise pipe on my Jetta for a DV relocation kit, and capped the end off, well took it for a test drive and it wouldnt drive good at all. RPMs we up and down, wouldnt hold any boost, engine kept trying to stall.. i pop the hood and find that the cap had popped off. That a 1.5" pipe opening, you minor stalling could be from the loss of vac due to the dipstick being out.
Anyway, i never read the PCV test posts.. most i saw were if you had oil around the oil cap on top.


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## syntrix (Aug 20, 2000)

*Re: (bwzimmerman)*

That does sound right. VW docs and personal experience show that if you put a leak in the crankcase like that, it will bleed into the rear PCV side.
Rear PCV side vents post maf, pre turbo, that means it's unmetered air.
Does that mean the front PCV side is leaking? Maybe, but if it is, it's not that large of a leak.


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## jasejtw (Jul 19, 2007)

so bwzimmerman, what your saying is after i cut the car off and i pull off the oil cap and on the underside the oil cap has oil on its surface. that would indicated a pcv issue. cause everytime ive ever taken the oil cap off there has been some oil on the underside that faces down into the engine. this means i could have pcv issuses?


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## [email protected] USA (May 17, 2007)

*Re: Ok, pull dipstick, engine starts shaking, means bad PCV?? (jasejtw)*

A brand new 2.0t rolling off the assembly line will stumble and stall if you pull the dipstick or open the oil cap. It is not an accurate test of PCV function.
At idle PCV gases are being drawn into the engine via the intake manifold. If you now open the oil cap or remove the dipstick you have drawn in unmetered air and it leans out the engine to a point where it can't run so it stumbles if its just a little air. it will usually stall if the oil cap is opened.


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## crew219 (Oct 18, 2000)

*Re: Ok, pull dipstick, engine starts shaking, means bad PCV?? (jasejtw)*


_Quote, originally posted by *jasejtw* »_I've read a lot of topics about bad PCV valves (sry to start another one), and i have read several ways of checking to see if the pcv is bad. But one method i've read is while the engine is idling to pull the dipstick up enough to break the seal with the crankcase, and if the engine starts shaking that means the PCV is bad. Also I have read to crack to oil cap while running, basically tests the same thing. Well i tried the diptick momentarily today and sure enough it started shaking. So do this definitely indicate a bad pcv vavle? or am i misinformed about this method of testing? and why does it make the engine shake is the pcv is bad and you break vaccuum on the crankcase system. Basically how its works so i can explain to the dealership the reason why this means my pcv vavle is bad. Im a logic way. Any input is appreciated. 

You're introducing a vacuum leak. Quite normal. 
Dave


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## jasejtw (Jul 19, 2007)

Ok well thanks. i have been misinformed.


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## bwzimmerman (Jun 16, 2007)

as far as a test for a PCV problem, only way I heard was if you had excess oil coming from your oil filler cap. If theres oil on the cap I wouldnt think you should be alarmed.. i could be wrong, most my info is from browseing these forums religiously everyday.
Anyway, I am sure someone can answer that for you. I highly recommend the EJ PCV fix.. there are a few DIY kits around, but they are made with plumbing parts. The Eurojets kit is very nice. Thick silicone and stainless steel vavle. If you still have stock intake you would have to modify you engine cover a bit to make it fit. (pretty easy, and doesnt affect the outter viewible part of the cover or the air box. I had pics of my modified engine cover on my car with EVOM intake and EJ PCV valve, but the thread is in the black hole due to me trying to sell a handgun. lol.


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## T1noandaudi (Jan 8, 2006)

my car is 06.
can i actually go to dealer and ask them to do a check ? even tho my car docent throw code.
i do have excessive oil burning tho. had to top off oil every 2k-3k


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