Hi, I’m new on here. I’ve previously had an 2002 s3 which was great fun but changed to a civic diesel as was doing a lot of miles, very reliable but not so much fun to drive. Doing less miles now. I’m considering a 2015 S3 2.0 TFSI sportback Quattro manual. Independent dealer selling with FSH, has 99k on clock. Is there anything I should look out for, is there any Audi advised maintenance due soon? Also what is the real world mpg?
Thanks for any help 

Welcome Robert,

If I was in your situation, I would be more concerned about this car’s history of faults, before worrying about what might go wrong.

Have you:- 

Done an on line DVLA vehicle check to see when the last V5 was issued - if recent, could be due to a returned faulty vehicle?

Carried out an on-line MOT history check? 
Actually seen copied evidence of the seller’s claims re. service history? 
If everything still adds up - pay £9.99 for a VCheck car history report. This will give you important information inc. whether it’s been through auction/s. 
Please let us know how you get on.

Regards,

Gareth. 
re. ongoing servicing, what is your anticipated annual mileage? 

The car is 10 years old, so you want to go through its history properly. If you or a friend have access to VCDS, I would scan the car too. If it’s had long service intervals, find another.

Maintenance wise, change the oil every 5-8k miles, air filter and pollen filter annually.

Gearbox, suspect S Tronic, so needs done every 38k miles. In addition it will be Haldex unit, so needs done every 20k miles. Audi just drop the oil, but pretty sure there’s a mesh filter in there that needs removed and cleaned. Search for Dave Sterl on YouTube.

1 hour ago, Magnet said:

everything

Thanks for the reply and info. I haven’t checked those but will have a look. The dealer says it’s had one owner from new. Looks clean and un-pimped! Will be doing 10k/yr approx. Do you have any idea on MPG? Thanks

59 minutes ago, spartacus 68 said:

Thanks for the advice. I’ll check with the dealer re the service intervals. I don’t have access to a VCDS, would rac/aa inspection have one if I get them to look it over, as the car isn’t local? Thanks again 

4 hours ago, RJG1 said:

Thanks for the advice. I’ll check with the dealer re the service intervals. I don’t have access to a VCDS, would rac/aa inspection have one if I get them to look it over, as the car isn’t local? Thanks again 

RAC have three levels of reports with most comprehensive one with diagnostics. However not cheap at £260 or so.

Watch out for third party warranties, some will recommend service every 6 months which isn't practical.

That said if you're doing 10k average. An oil change every 5k may work in your favour.

VCDS can be purchased from Gendan. You'll need laptop to run it. Bear in mind Audi main dealer will charge you £150 or so to scan. Three VIN Version is fine.

 

4 hours ago, RJG1 said:

Do you have any idea on MPG? Thanks

Manufacturer says 40mpg, real-world probably 30mpg with light right foot.

If you bear in mind that the seller is telling you the truth when you have actually seen the evidence in writing, or when he his lips closed, you won’t go far wrong. 
If you don’t methodically carryout the pre-viewing procedure I suggested , and have the evidence to hand before you set off to view the vehicle, two things can potentially go wrong:-

You will fall in love with it, and buy it irrespective,  and you know what love can do.

You will regret your purchase. 
There is a third possibility that you decide not to buy it after spending money and time to go long distances to view it. 

I have just bought one with 85k on the clock. Drove so nice on the test drive and the history looked good. About a month after the purchase it has a few issues with it. I’d had the diffs and Haldex serviced due to lack of. Then my mechanic after the service told me it has a few problems with her. Not the diffs or Haldex may I add. The pcv valve being one issue  which is possible causing maf problems as well. There is also an air leak which is not helping. Yet to locate that problem. Will keep trying to overcome these small issues as I absolutely love the car. Just not the small niggles she has. 

10 hours ago, RJG1 said:

Thanks for the reply and info. I haven’t checked those but will have a look. The dealer says it’s had one owner from new. Looks clean and un-pimped! Will be doing 10k/yr approx. Do you have any idea on MPG? Thanks

About 30 with a very light foot. 

I recently bought a 2015 S3 3dr, unmodified. 70k mls. For mpg, in Efficiency mode on the mway I can manage 34mpg @70 average. And 32mpg @ a higher average, going with the flow of traffic.

Having said that it's pretty boring to do so but if it saves money on the commute then so be it! 

Edited October 12, 2025Oct 12 by DUBble chin

I have an 18 plate, stolen recovered, S3 and it’s brilliant. It did have full audi S/H and I did all the checks mentioned in posts above before I got it. I get 40-42mpg, 45 a few times on a good warm day, cruising on the motorway at 70 in economy mode (dull but economical). If I cruise at 80, it drops to 35-38. Winter it’s around 4mpg less. Round town I use auto mode and it’s low 30’s. I use cruise a lot, even round town as I find the gearbox keeps the low gear. I’ve done 20k and it it’s not missed a beat. Gearbox, haldex are important to get done on time and oil I change at 8k. I am surprised at how much I enjoy it, on the open road in the country it’s great fun and unbelievably quick. Not sure on the engine differences with the facelift between the 15 and 18 plates, but that’s what get on mine. 

Hello Robert,

So what did your checks come up with, and do you intend to buy it? 
Regards,

Gareth. 

On 10/17/2025 at 9:21 AM, Magnet said:

Hello Robert,

So what did your checks come up with, and do you intend to buy it? 
Regards,

Gareth. 

The one I had seen had only had the haldex serviced once in its 100,000 so didn’t go to see it, thanks for everyone guidance and advice. I have to find a car asap as mine was was written off and only have the courtesy car for a limited time from the at faults insurance. Looking at prices for a solid S3 example and what the damage engineer assessor is offering despite my examples of similar cars, I’ll have to cut my cloth accordingly and go for the cheaper (less fun) option of another older civic.

Thanks for everyone’s input, it’s much appreciated.

On 10/11/2025 at 10:14 AM, spartacus 68 said:

Thanks for the advice. I’ll check with the dealer re the service intervals. I don’t have access to a VCDS, would rac/aa inspection have one if I get them to look it over, as the car isn’t local? Thanks again