A4inAR

Let me start by saying I know nothing about cars in terms of maintenance. I can change a tire and air filters. Beyond that I follow the maintenance schedule in the car's documentation. So long as my car is under warranty I take it to the original dealer. However, in this case it could turn out to be a problem.

I have a 2012 A4 Quattro automatic.

Everything was fine through December 2013 when I had the 25K mile service.

600 miles later the check engine light came on. I took it in and they diagnosed it as a bad upper crankcase pressure regulator. A new crankcase pressure regulator was installed under warranty.

A little over 1,000 miles later the car told me to add more oil. I had no idea what kind of oil they were using so I parked it over the weekend and took it to the dealership Monday morning. They topped it off and sold me a liter of oil to keep in the trunk should it ask for oil again.

Around 1,000 miles later it told me to add oil. Following the instructions in the manual I did so. It took the entire liter.

Today I went back to the dealership to buy another liter of oil. I took the bottle with me so they could see exactly what I needed. The gentleman at the service department referred me to the parts department across the street at their sister dealership. He said that is where they keep the stock. I went there and gave the gentleman the bottle. A few minutes later a woman returned with a new bottle of oil. This was a quart, so the bottle was a different size, shape, and cap color (though still the same brand synthetic). I told her this wasn't exactly what they gave me across the street last time. She said it was just a new bottle design. I told her I was pretty sure the numbers were different. She pulled my old bottle out of the trash and took a look at it. At this point she said, "Oh, you have a diesel." I assured her I did not. She informed me that what I had was diesel engine oil. At that point she asked if I put that entire liter of oil in my car. I told her I had because it was what the service department across the street at Audi sold me and my car took the entire liter to tell me to stop adding. She said it would *probably* be OK. I thanked her, took both bottles and left.

I went back across the street to the Audi service department. I explained that I was in about 1,000 miles ago for a top off and they sold me a bottle of oil for the next time it asked for more. I informed them I used it per their instructions and that of the owner's manual, only to find out what I had been sold was diesel oil. The service rep said it would *probably* be OK since what they sold me was heavier weight than what it required, being 40 instead of 30. I looked at the bottles and told her she had it backwards in that they hold sold me 30 when what was called for was 40. At this point she called her manager, so that she could take both bottles and go across the street to talk to the head of their service departments.

A few minutes later the service rep gets a call. She says the head of their service department has informed her it would *probably* be OK but they could change my oil at that time if I wanted. She said it was not clear yet whether that would be free or on my dime. I told her I would defer to the dealership's expertise.

At this point she began asking questions about oil consumption, when they topped it off, when I had to top it off next, how much I put in, etc. She then pulled up my service records and got my VIN. At that point she got back on the phone with the head of service across the street. When she came back to me she said they needed to run an oil consumption test. She explained they would need my car for a day next week. When they were finished I would drive it 600-1,000 miles then bring it back. At that point they would do another test. Depending on the result of those tests she said they might need to replace the pistons, rings, some other parts, and perform a software update. She assured me there would be no charge to me for any of it. I told her that would be fine and the appointment is now booked.

I've seen the oil consumption thread pinned to the top of the forum, and realize that dovetails into my issue somewhat. But I'm concerned about the wrong oil being put in my car in terms of just when did it start and at what volume. It could be coincidental timing, but the only issues with my car began within a few hundred miles of the 25K service. It's been about 300 miles since I put the liter of diesel oil in and it shows roughly 50% between the Max and Min lines on the MMI. I'll note my normally chrome exhaust tips are now black as coal as well. Again, maybe these things just start to happen around 25K and are normal, but I'd rather be safe and ask.

Has the dealership made a mistake that has had an impact on the long term reliability of my car? I only have 1 year of warranty left so this concerns me greatly.

Many thanks for any advice.

gsjohal

Hi.
I litre of wrong oil is not sufficient to cause any problems. It is more important that the right oil goes into a diesel, as it is a low ash oil which is required to prevent the particulate filter from clogging.
There is a known oil consumption issue on these petrol engines for which the repair is replacement pistons/ rings. However Audi confirm that the oil consumption is excessive by carrying out a consumption test. They carry out an oil change, adding the correct weighed measured amount into the engine. Next they ask the customer to take the vehicle away and return after driving 600miles. Finally they drain the oil and weigh it again, calculating a consumption figure.
They usually mention that if it isn't excessive, the customer pays for the test.
Rest assured regardless of the warranty, Audi should honour the repair if required.

A4inAR

Thank you for the reply. I feel better knowing about the diesel oil likely not being a problem.

The possibility of replacing the pistons and rings scares the heck out of me. We got rid of my wife's last car because the head gasket needed to be replaced. I had very little confidence in the long term reliability of the vehicle once the engine had been taken apart. But that was with an older car with high miles. Having it done to a newer car with low miles make me even more nervous.

I'm thinking very hard about getting rid of this car while it is still under warranty.

shs92645

the repair is very common....thousands of these engines have been done....you end up with what amounts to a new engine, so go for it.

gsjohal

As a former Audi Technician, I have carried out many of these repairs.
As the previous poster mentioned, you end up with a rebuilt engine, which has become quite a routine repair. Its a repair customers push for if anything, and will be a fully warranted repair. You'll get a loan car whilst it's repaired too, so it's a no brainier, go ahead with it.