As the title says I'm looking into purchasing a 2013 audi S5 prestige. I was curious as to what kind of issues they have, what kind of performance upgrades I can do to it. Thank you in advance for your replies
I have owned a 2016 S5 since new. No problems concerning mechanicals (no engine or transmission problems). It is very reliable as long as it has a good maintenance record. Have the prospective car checked for Diagnostic Trouble Codes (DTC). Test all features to make sure they are working. Look for a rough shifting DSG tranny. Shifts should be smooth and quick with no hint of hesitation. Check for fluid leaks (engine, brakes, diff, tranny). Have an independent Audi master tech do a thorough inspection on it including any outstanding DTCs.
As for possible mods, I have nothing to say because I prefer to keep my cars in mostly stock condition. I did do some brake and tire updates. No performance upgrades.
If you can get one that was built mid-2013 or later then it would have the latest generation DSG. But whatever version it has, it MUST have been serviced at no more than 38K intervals (that's the DSG service, not general service). As noted above, any less than smooth gearshifts can indicate a problem. Higher mileage engines can suffer from loss of cam drive chain tension (rattle at cold start) and engine mount failure. Other known issues include problems with the PCV (oil usage), crank pulley failure and in some cases premature cat failure (degradation due to heat).
As for performance upgrades I suggest that you check out APR's website. That's not necessarily and endorsement of APR (although I have used APR products and have been pleased with them), but I find that APR has a good range and provides good information, so a bit of time on their website should let you know what sort of performance upgrades are available for this platform.
You good see the mileage and the service history UNLESS you like to gamble!!! I purchased an unloved and neglected A5 3.2 years ago and I drove her from 100k kms to 200k without any major issues, I just changed tyres and brakes and normal service stuff. These are strong cars. My current 2004 S4 is now at 220k kms and she flies!!!
Have the steering rack looked at. Common failure on the 2013 models. I just bought a used 2013 S5 with 55k miles and fortunately for me I bought an audi extended warranty plan. They just replaced the rack which is a £3k job give or take.
They're prone to water ingress and eventually become noisey and fail. I imagine they were revised for later model years as I’ve only ever seen this effecting the 2013’s.
Other than that, check the oil consumption. Some 2013’s need updated piston rings from what I can gather. Currently monitoring mine but pretty sure this is a very uncommon issue on the facelift cars. Mines burning around a litre every 1800/2000 miles which I think is high but well within Audi spec apparently. PCV can fail also on these cars.
Water pump prone to failure at higher mileage so worth checking this also.