Oil in coolant solution - Audi A4 B7 BWE

Wanted to give something back to this forum; I can't tell you how often I find myself utilising the information available here. Its like a living Haynes manual.

So thank you to everyone who has helped me in the dark hours of owning a motor.

----

Car Specifics - Audi A4 B7 2007 2.0T FSI Q (Stock - except PCV revamp, and new Turbo diverter)

Right, so just before Christmas I was given this as a present:

Attachment 32536

Coolant light was shouting at me, and when I pulled over and popped the hood there was thick brown sludge everywhere and steam coming out from the block. Wasn't nice.

Immediately thought the head was away and was towed home.

Cleaned up the mess but the sludge was through everything and all the pipes I could remove had a 1-2 mm thick layer of the stuff caked on the inside. So I have no idea how long I was running about like this for however never had overheating issues.

I had no heating whatsoever and on cleaning what I could out the system, running the engine only resulted in overheating at idle. Used Torque android app to monitor the temp more accurately than the dash needle as it was too generic in comparison to the actual ECU output.

Kept flushing and flushing, but the oil just mixed again, and I think in the end I lost a total of 5 litres to the problem. This led me to assume the oil cooler was away. However to rule out the head gasket I had the block pressure tested and it passed (albeit it, cylinders 3 and 4 were slightly less, but this was diagnosed as just old age).

So I had the oil cooler replaced (approx £250 for labour and genuine parts) however still had the issue of the sludge. Again flushing did nothing. It was just too thick.

I ended up ordering a product from an Australian company called Liquid Intelligence.

Attachment 32538

Was about 80 euros inc. P&P - not sure why it was euros, the supplier was in England, called ILS Engineering. I actually need to give a shout out to the company because they sent me another liquid in error and ended up refunding the full price of the wrong product, plus shipping, and told me to just hold onto it.

This product was incredible and I cannot recommend it highly enough if you have similar problems - even if its just your heater matrix thats blocked. Within 40 minutes of running this in the coolant system I had full heat back and it had dissolved all the gunk which was fairly easy to drain after that. Don't get me wrong it took about 6 full flushes and a few days running in-between to get the milky solution out of the lines but in comparison to using water or washing up tabs etc as suggested on a few posts on this site it was incredible. I'm not posting any links up as I'm not sure if this is allowed but google it and look at the details.

For anyone trying this, all I did was remove the top and bottom radiator hoses and ran the garden hose through the expansion tank, and the radiator until ran clean. Its fortunate that the radiator inlets are the perfect size for the hose. Not sure if this is the same on all models. Also put a new expansion tank (£15) on as he original was filthy and I couldn't clean it up well enough for my liking.

Attachment 32537Attachment 32539

I had taken lots of photos to post up a mini tutorial however I'm limited to 5 uploads. But there are great guides on doing all this stuff and even the oil cooler if your mechanically minded. I'm normally good at working on the car but for this one I trusted the professionals as I couldn't afford to have the car sitting on the driveway whilst I figured out why I tackled a job I couldn't do - therefore didn't risk it.

So after 4 weeks, £400, and a lot of water I can only conclude the post with a picture that says it all:

Attachment 32540

Hopefully this help someone at some point. Good luck and thanks again everyone for the help.

I'm having the same issue and debating if I should change the oil filter housing which is plastic or the oil cooler which is a metal. Can you advise me if you changed one or the other or both thank you very much

Sorry to hear your having the same issues. I would check you oil reserve for gunk. There was very little on the cap but a lot on the lower dip stick. So chances are you'll have breached both the water-oil and the oil-water gasket on the oil cooler. I certainly had so a mandatory oil flush i felt was necessary and therefore oil filter change before the fresh oil. So either way you'll be in and about the housing. If its not cracked or damaged your good.

Id start with the oil cooler. Eurocar parts have an aftermarket for about 100 last i checked. And its def. a DIY job if your confident.

After that remove all the pipes you can and start cleaning it all up. I really do recommend the stuff i mentioned in the original post because it will save you 3 days coming to conclusion that water and soap do nothing. This emulsified all the oil in minutes and just drained out. The fluid stay a milky colour until all the product is out. Then just top up with G13.

Anythint else i can help you with just let me know.

In the meantime watch your oil pressure if your running it idle. Its eats some amount of oil.

Having the same problem 😕 but mines black Black. Fitted new oil cooler and still filing the tank Black 🤔lost.

The oil contamination is extremely difficult to get out so it may be residual.