Oil filler cap - pressure

[davidlandy]

Also posted in the Audi a4 section but seeing as its the same engine, thought I would post in here too!

I today removed the oil filler cap on my 2002 1.9 tdi 130bhp A4 and there was quite a lot of pressure there, so much so that if I undid the cap it would just about stay in place, and a little 'heat' smoke and chuff a bit. It was at normal working temperature so quite hot and isnt smoking, overheating or running badly.

Is this normal for one of these engines?

[martin1810]

Don't worry about it. The average diesel engine lets more pressure by than a similar petrol engine as the compression is so high.