Really dumb question here..

[Axl Rose]

No long introductions..if you remove the oil filler cover while engine is running..is there a head gasket problem when the engine sounds the same or when it changes?
I'm not going to excuse myself..[&o]

 

[peanut]

uh!?[]

I guess you mean is there any significance if the engine noise changes when you remove the oil filler cap yes ?could we know what car ?

 

[Axl Rose]

That's what i mean..the car is 1985 944 Lux..

 

[DivineE]

Engine revs should drop slightly when oil filler cap is removed. More important signs though would be..

1. Goo in the header tank.
2. Pressure in the header tank (30mins or so after the engine has been run warm then turned off there should be little or no pressure, if there is alot of pressure still then this is v.bad)
3. White smoke from the exhaust which looks like early morning mist but lingers for alot longer (v.v.bad)
4. Excessive Goo under the oil filler cap (this is a less reliable method on a 944 as moisture sometimes collects and looks like this anyway)

 

[peanut]

ORIGINAL: DivineE

Excessive Goo

what ? you mean like snot ? hee hee............ I guess you mean emulsified oil lol []


I have never removed the oil filler cap whilst the engine is running cos on most cars you and the entire engine bay tend to get liberally covered in 1/2 gall of Duckhams 20-50 in no time at all [] but on the few times that I did the engine noise increased quite a bit

 

[rob944s]

HI Axle i am not sure if this will help you but[8|], when the filler cap is removed the air intake pressure is reduced because there is a breather pipe from your cylinder block to your air box which takes the unburnt fuel and air gasses that will esacape down the cylinder bores to the crank case, these gasses are re-directed to the air box for re-ignition and put back into the combustion cycle, thus when removing the filler cap the path of least restricion lets these gasses escape through the filler cap neck resulting in lower intake pressure dropping the revs at idle, thats going on the assumption your not doing 125mph when removing the cap if so,
A................................I maybe wrong.....
B................................do you have a short video on you tube so we can see you do it....[]

 

[Axl Rose]

Thanks for all replies..just wanted to make sure if i remembered it right..

My white car's going to be off road for a while now..as mayo on dipstick and water on oil filler cover speak for themselves..pitty - that means that i'll have to push the re-spray in future again..