A4 2.0 petrol oil leak, help please

[Cpt.cliff]

Hi guys,I'm new to the site so go easy, I was on my way home when I had smoke coming from the engine bay, stopped and could see oil was coming from a hole at the back of the head all over the cat and burning off. Got the car home and had a closer look, it's a round hole to the left of the temp sensor and is 26 mm in diameter. Ordered a part from audi that's a 22 mm core / freeze plug so won't fit my 26 mm hole. The question is do I need a 26 mm plug or is there something else that go's in the hole that's fallen out. I have added these pics, first one the engine seconed and forth the hole in question and the other is where it is. Thanks

 

[Mike_B]

Well, without taking off the big black pipe, I can tell you that mine appears to have a black plug - which is slightly oily. It's a little difficult to take a measurement off I'm afraid. I'd be talking to Audi again - - -

 

[Cpt.cliff]

Thanks for looking mike, it's gone in to my local Indy today for the to look at but I'm sure it's just a plug of some sort. I have a mate that works in parts at audi and supplied me with the 22 mm core plug but did say there was a lot of different sizes. Guess i will find out tomorrow. Will message back when I do as no one seems to no for sure.

 

[Cpt.cliff]

Ok it's been in and it was a rubber plug on the back or the cylinder head, £2.18 from audi. Over the years it's degraded and come loose in turn spitting oil over the cat. Easy fix in the end. Thanks again mike