Hi All,
23i 2009
I recently had my car to the local indy who told me that when they tried to remove the oil cap from the running engine it was difficult die to a negative pressure inside the crankcase.
They told me that the engine breather is integral to the cam cover.
As a result they changed the cam cover which was quite expensive.
The other day while cleaning the engine I decided to start it and see if it was still hard to remove, it did 'suck on' a little bit but nothing major.
My question is, should internal engine pressure be positive/negative or the same as atmosphere??
Seems to me slightly positive considering combustion leakage etc..
Any ideas chaps??
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Internal engine pressure
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- Senior Member
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Internal engine pressure
Mark
Plymouth
E89
35i
Carmine Red
Black leather
Plymouth
E89
35i
Carmine Red
Black leather
- GuidoK
- Lifer
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- Joined: Tue Aug 17, 2010 1:37 am
- Location: all over the place
Internal engine pressure
Should be negative due to PCV.
If you want to know if the valve cover was changed for a legit reason: now way of telling now; the part is gone for a proper diagnose.
If you want to know if the valve cover was changed for a legit reason: now way of telling now; the part is gone for a proper diagnose.
Z4 3.0i | ESS TS2+ | Quaife ATB LSD | Brembo/BMW performance BBK front/rear | Schrick FI cams | Schmiedmann headers+cats | fully polybushed | Vibra-technics engine mounts | H&R anti rollbars | KW V3 coilovers | Sachs Race Engineering clutch
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- Senior Member
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Internal engine pressure
As above, slight negative pressure
- Smartbear
- Lifer
- Posts: 13685
- Joined: Wed Feb 05, 2014 6:54 pm
- Location: a barn in Somerset
Internal engine pressure
Usually when the pcv is starting to go defective the car starts to burn more oil with sooty tailpipes etc, was your car exhibiting any of these symptoms?
Rob
Rob
e89 Sdrive 20i, plenty of mumbo & good economy-the thinking bears z4
e89 Sdrive 30i, this ones busted, pass me another...
e85 3.0si sold