Every new car powered by a combustion engine Audi will launch in the next three years will be the last of its kind as the German luxury brand intends to introduce only EVs from 2026. As evidenced in spy shots from northern Europe, the S4 will get an ICE finale, complete with quad tips to mirror the other S-badged performance cars. It appears to have the full production body and final headlights but those basic taillights are a provisional setup.

It's unclear whether the prototype has a diesel engine taking into account that the European version of the current S4 (and larger S6) utilises a TDI powertrain. The 3.0-litre V6 diesel is offered for both saloon and wagon body styles and comes with some ghastly fake exhaust tips. In the United States and other markets, Audi sells the vehicle with a petrol V6.

The diesel-fuelled S4 already has a mild-hybrid system, so logic tells us its replacement will also have some form of electrification baked in. Here's hoping it won't downsize to a four-cylinder engine like it has been the case with the Mercedes-AMG C43. Speaking of engines, there had been some rumours about Audi demoting the next-gen A4 to the MQB platform and transversely mounted engine but that won't be the case.

While the exterior styling appears to be evolutionary (with new flush door handles), expect a revolution on the inside where previous spy shots of the regular A4 Avant have revealed a completely reworked dashboard. Unfortunately, those of us who prefer neatly integrated screens are in for a disappointment since the next-generation model will have a pair of displays slapped onto the dashboard.

2023 Audi A4 / RS4 Avant spy photo
2023 Audi A4 / RS4 Avant spy photo

Oddly enough, the A4 and S4 prototypes have so far been caught testing exclusively in the more practical estate guise. Audi hasn't said anything about dropping the saloon, but let's keep in mind the next Volkswagen Passat will be an estate-only model. Saloons have fallen out of favour, although we're still having a hard time believing there won't be an A4 saloon. On the other hand, it kind of makes sense since the Ingolstadt-based brand also has the A5 Sportback.

The wraps should come off later this year, and logic tells us Audi will initially unveil the regular A4. The S4 and RS4 are expected to arrive later in 2024, with the latter confirmed to adopt a plug-in hybrid powertrain. RS models with four-cylinder engines have been officially ruled out, so the super estate should still have a V6.