Mass Oil Leak :(

[HuwSy]

I seem to be loosing a lot of oil, lost about a litre for 100 miles/5 hours run time. It doesn't lose any standing still and cold. When the engine is still warm or running it drips off the plastic tray underneath a drip every half minute or so. Whilst driving it must have been coming out faster.

Having taken the tray off I can see the oil dripped all over the exhaust and bottom of the engine where its running down too. But I cant see where its coming from as it comes from higher up the engine somewhere. There's a small collection oil between the oil filler cap and where cables go in to the side of the block which keeps reappearing after being cleaned off, and on part of the cam cover seal here. And there's some oil dirt sludge combo further back near the PCV but its not fresh looking. Neither of these look to be enough for the amount being lost though and its not making blue clouds, smelling of burnt oil at the exhaust or passing into the water. On the other side of the block where the turbo sits looks completely dry.

Before I start stripping bits off the car has anyone any ideas where it could be coming from, where Im best looking or anything else I might be able to see without disassembly.

Thanks

[simesf]

Hi I have just had the same symptoms on my RS2. The leak was coming off the left hand side of the engine block. Smells of burning oil when engine hot and a small stain of oil on the floor when parking after a run.
It ended up being the oil pressure switch. You may need a torch to see properly as there's a white rubber protection over the switch. The plastic part of it where the contact is attatched was leaking. It only cost 13 euros from the main dealers but was a nuisance to get at. Thin arms and a multitude of socket set bits with a 24 mm drive should do the job. I removed only the dipstick tube. Everything fine now. There's a thread with quite a few photos and help on this forum.
The oil near the filler cap is probably oil spilled from the last top up.
Hope this helps

[TimE-J]

I'd check the oil pressure switches underneath the inlet manifold as well.

[HuwSy]

Ok thanks for these. Will take a look again tomorrow when it's a bit lighter out.

[macspring]

Hi I have just had the same symptoms on my RS2. The leak was coming off the left hand side of the engine block. Smells of burning oil when engine hot and a small stain of oil on the floor when parking after a run.
It ended up being the oil pressure switch. You may need a torch to see properly as there's a white rubber protection over the switch. The plastic part of it where the contact is attatched was leaking. It only cost 13 euros from the main dealers but was a nuisance to get at. Thin arms and a multitude of socket set bits with a 24 mm drive should do the job. I removed only the dipstick tube. Everything fine now. There's a thread with quite a few photos and help on this forum.
The oil near the filler cap is probably oil spilled from the last top up.
Hope this helps

Would definitely agreed with this. A deceptive amount of oil can get out through this switch. Nearly seized my engine as it was "using" so much oil and I forgot to top it up. The head gasket went a couple of thousand miles later, no idea either way if the two items were related, but took the "opportunity" of the blown head gasket to take the whole engine out of the car. The engine stripped for a full inspection and a possible rebuild. During the inspection there was some scoring on some of the main bearing shells on one of the cylinders that one might think should not be there, when it was not on the others ??

Macanmar may be able to expand on what exactly was found, but in any event a different block and head were used by JP to rebuild an engine for that car and the "original" engine had the bottom end tidied up, parts replaced, and will go into the back up S2.

Don't worry it's hard for me to remember which head / block is which.

In summary though, get a decent oem new white oil pressure switch and copper crush washer from the dealer and replace, cheap at twice the price in the long run.

As mentioned it is a PITA to get to.

Kind regards.

[UrS4boy]

Oil pressure switch and sender info

As others have suggested, it is most likely the simple white pressure switch under the intake manifold, as discussed in this post (with PNs) and shown here (for an RS2):

http://forums.quattroworld.com/s4s6/msgs/96161.phtml

[macspring]

Dave,

Your links are great, thank you again on behalf of the rest of us and myself.

Makes it easier to understand these cars and to keep them in good order.

Kind regards.

[newsh]

A Friend of mine just had this switch go on her A3, lost a whole load of oil very quickly and had to get recovered as it seemed stupid to put in several litres just to drive back from the supermarket.

[Knight Rider S4]

To clarify , Husky you say it burns on the exhaust?..if so the oil pressure switch is on the otherside of the engine so maybe not that , I would check the oil feed pipe to the turbo and see if that is spraying oil out .

[newsh]

I think he said exhaust side was dry? maybe getting blown back when driving along?

[UrS4boy]

Your links are great, thank you again on behalf of the rest of us and myself. Makes it easier to understand these cars and to keep them in good order. Kind regards.

I try to help. Sometimes I win, sometimes I don't, but I try.

You're welcome.

I've got a couple of new ones I'll post up today.

[HuwSy]

Thanks for the help and the useful pic, having looked I can see a lot of oil around the center of that image. Although cant tell if its off the pressure switch or the pressure sender and cant reach either as theres too many radiators and pipes (having air con i think makes for an issue) Is it the pressure switch that is prone to going wrong, or the sender or the gasket on either of these as I cant get the part today around here but would have many a gasket available if it is only that until I can get the parts tomorrow before I start dismantling? Thanks.

[HuwSy]

Oil pressure switch dead it was. That's swapped out for another audi 80 thats off the road, now it ran for about 5 min then stopped dead can't find anything that's not been reconnected but can't here the fuel pump. Where is the pump anyone?

[driftin jo]

pump is in the tank, access hatch for it is under the boot carpet

[TimE-J]

If its a coupe then its under the boot carpet under the large metal plate.