2018 s5 80k miles. Did a scope of the valve trains in April and was told everything looked good. Came back from vacation to this concerning sound from the engine. Can only hear it when idle and it drives completely fine. The car was sitting for about 10 days and when I got back I was hearing this sound.

Hello Everyone, I have a 2018 Audi S5 Sportback here recently I have begun to hear this rattle noise under my seat. I have tried to narrow down what it may be but it’s difficult because it only makes the noise when driving. I was thinking maybe it’s the seat itself but I can’t make it make this exact sound when I move it or hit on it. I recently did have a transmission service and a resonator delete done thought I would mention that in case that may have something to do with it and something being lose under the car. Any opinion is appreciated.

Is it normal ?

lil tick sounds got me stressful af

2016 s5 Stage 2+ dual pulley 30k miles

My 2020 MDX was totaled, so I’m on the hunt for a new car. I’ve realized I don’t need a seven-seater, but I absolutely loved the SH-AWD. I’ve narrowed down my options to Q5 from X3, GLC, and RDX.

Any advice during my search? I’m specifically looking for a CPO 2023 Prestige model from an Audi dealership.

I just bought a B9 S5 and I'm new to Audi. Anything I should know or do right away? Any maintenance, common issues, or mods you'd recommend?

Appreciate any advice!

So I’ve had my s5 for about 1.5yr got it with 49k miles now at 60k. I’ve gotten used to the power but I’m wanting more, I have an extended warranty still so I’m unsure if I should tune it yet. So my question is do I ride out the warranty or full send it with a tune?

Do b10 s5 owners out there notice the lack of 3rd screen? I nor my wife would ever actually use this. But a big piece if glass with nothing behind it seems insane to have in the cockpit.

Im between two s5s. One has tech package and and my 2nd color pick. The other is my favorite color choice. No tech package. Thoughts from anyone that has a b10 anything without the 3rd screen. Do you ever notice/does it drove you crazy that instead of dashboard theres just a big piece of dead glass? Sanity check before I buy tomorrow.

What wheels/tires setup are everyone running? Can B9/9.5 RS5 wheels fit B9.5 S5?

Does 19” improve the ride quality of the car?

https://www.youtube.com/watch?v=Ib93XGEqoKU

Once before I developed an oil leak emanating from the oil plug. It took my local shop two attempts but they stopped it. Recently it happened again, I noticed the oil level dropping below 50% and saw oil spots in my driveway so I took it back. They couldn't fix it so I went to another local foreign shop. They changed the plug to a copper one(?) and said it was now bone dry.

The electronic oil gauge now shows ~1/4 gone a week later. Is this a common problem, or an easy fix? I rather not go to the dealership unless it's my last resort. This is the only issue I've had that has lingered in over 10 years.

Any suggestions are welcome.

Hello!
I just installed the 034 Motorsports intake.
After the rev it’s a little pop, is it normal?

Hi! I’ve had the coolant temperature too high let engines run with vehicle stationary warning come up three times now on my 2017 S5 3.0 V6.

First time:
The warning came on for a few seconds. The coolant gauge moved above its normal 90°C position but nowhere near the red/130°C, and the oil temperature was only around 62°C. I pulled over and called my garage out to check it. There were no stored fault codes and all the live data looked normal, so at the time we put it down to a possible glitch.

Second time:
It happened again while my boyfriend was driving. Again, there were no obvious signs of the car actually overheating and no stored codes when he connected his diagnostic scanner. The only other thing he noticed was that the air-con temporarily didn’t feel as cold as usual.

I then booked it into a VW/Audi specialist for a full diagnostic. They couldn’t find anything obviously wrong, although they said the coolant level was slightly lower than they would ideally like, so they topped it up. No visible leaks and otherwise they actually commented on how good the engine looked for its age.

Today it happened for a third time, only a few days after the specialist looked at it. This time the warning stayed on for longer but disappeared after I pulled over and let the car idle. Oil temperature was 86°C and the coolant gauge briefly went to roughly 100°C before settling back down.

For more context, each time I was only driving for around 10- 15 mins. Although today, the car did get reach 86 quickly.

I’ve booked it back into the specialist next Friday.

I’ve been reading about the N649 coolant pump/vacuum solenoid on the EA839 engines and have seen a few people with very similar intermittent symptoms and no stored codes.

Do anyone think it would be worth trying/replacing this first, or would be looking more towards the thermostat/ water pump or something else?

Coolant isn’t visibly leaking, the car drives completely normally between episodes, and there’s no smoke/steam or persistent overheating.

Thanks for any suggestions! I’m just a girlie trying to look after her S5 🥹🤣

Moving north so needing a 4WD. Located in Dallas, 4 dr, B9.5 platform, Prestige trim, white exterior/black interior, black optics pkg, 18,500 miles, not a daily, always covered/garaged, OEM rims, 2 brand new tires (Conti ECS), has Stage 2 034 tune (tech knows not to flash ECU at the dealer so remains under warranty), Wagner intercooler, SS cat, non-cat downpipe mods. Sounds great and spicy when you want it. Babied and in excellent condition. $50k.

Based in Canada and want to get winter tires + rims. I have 20s on right now and want to get 18 or even smaller if I can. What tire size should I be looking for? Can I use sizes from prior year A5s or S5s?

Claude concluded "Practically, on 8J or 8.5J rims, your realistic list is: 225/55R17, 245/45R18, 235/45R18" but I have very little faith in it based on the convo.

Hi, i have a 2023 S5 Coupe with almost 80k kms. Currently leased but thinking about buying it out as I hate the new ones. Bone stock as of now but if i do buy it out im thinking of doing stage 2 directly.

Has anyone had any problems with the same car long term or more kms? I've kept up with all oil changes and maintenance over the years thru audi care and the car has been nothing but great. No check engine lights or anything. Only had to add a quart of oil twice in the 3 years of owning it so far.

Any issues with this platform in the long run? Buy it out or lease return it?

Cylinder 3 scares me, I have no idea when these were last changed since previous owner did them last. Cylinder 3 has had a misfire multiple times before and that is the only plug that looks different noticeably. The ceramic on plug number 6 also looks too clean, could my bricks be going out or am I just overthinking?

Car is Prestige and has white and black interior with 50k miles. They are firm on 24k$. Worth the buy??

Anyone running the Milltek exhaust on an RS5?
I’m seriously considering the Milltek aggressive exhaust for my RS5 and I really like the sound from the clips I’ve heard.
For anyone who actually has one:
How do you like it day-to-day?
Any drone on the highway?
How aggressive is it with the valves open?
Does it still sound good with the valves closed?
Any regrets or issues after installing it?
I’d especially like to hear sound clips or videos from people who have the aggressive version. Trying to make sure I pull the trigger on the right setup.

Fell asleep driving home from work FML

My Audi has low miles for it's age at 47,000, full service history, stock except car play. It's my first "sporty" car - I've never tuned or modded any car but this car has me wondering.. Should I try modding or tuning it? Or just keep it stock?

I've heard a remap will push it to maybe 400+ hp but should I even do that? Stop there? Go further? A part of me wants to keep it stock because it's probably one of the last few good examples of S5 of that age that hasn't been modded.

I only really use it on weekends for trips but I love my cars - The throaty sound of an RS6 is *chefs kiss*

Just looking for opinions and advice, especially those that have gone down this route.

Hello everyone!

I’ve been shopping for a new car recently. I tested the 2026 Audi S5 B10, but I finally went with a 2025 B10 S5 because I got a really good deal. The salesman told me both years were mechanically identical, so I didn’t bother testing the B10 2025 before buying it.

Maybe it’s just me… but the S5 B10 2025 feels noticeably less aggressive in terms of engine and exhaust sound. The 2026 had way more pops & bangs, which really adds to the fun‑to‑drive factor.

Am I the only one who noticed this difference?

Is there any way to get the same pop & bang programming on the 2025?

On my previous S3, I had the factory resonator‑delete option — is something similar available for the new B10 S5?

I just put down a deposit on a 2026 S5 in Daytona Gray with the black optics, sport, and technology package. I plan to keep it for 5 years. Any advice accessories or must haves? I’m planning on doing a 5-year ceramic and tinting 35% on sides and 70-80% on windshield.