Powertrain details for the next-generation Audi A4 remain a mystery. However, new spy shots of the A4 Avant captured the model with a charge port, hinting at the car's expected engine lineup. Sadly, Audi continued to hide the car under a camouflage wrap, concealing the rest of the design.

The charge port is quite visible – a slab of black plastic above the rear wheel well. Audi hid the fuel door on the other side, making the difference even more noticeable. Our spy photographers actually captured two different A4 Avant wagons testing in the snow. The second one didn't reveal its charge port to our camera, but it wore high-voltage stickers on the front, back, and sides.

Gallery: Audi A4 Avant Plug-In Hybrid Spy Shots

While the photos provide more information about the A4, we still don't have any specifics. There have also been conflicting rumors about the model's direction, with some saying that the turbocharged 2.0-liter from the current-generation car would carry over to the new model with some tweaks. However, others have suggested that Audi would add electric assistance to the A4 lineup, which seems likelier in the wake of these new spy photos.

The automaker confirmed in 2019 that the hotter RS4 Avant would receive a plug-in hybrid setup, but we don't know much about it. The A4 in the photos above lacks RS models' typical oval exhaust pipes. We have also spied the mid-level S4 Avant, and it seems Audi is keeping the car's 3.0-liter V6 under the hood.

The wagon's finer styling details are hidden with the camouflage. The car will receive a wider grille with a trapezoidal opening in the lower bumper. The two A4 Avants continue to wear stand-in taillight units. Spy shots of the interior showed off a dual-screen layout, with a narrow display behind the steering wheel for the driver and a larger one in the center of the dash for the infotainment controls.

We expect the next-generation A4 and S4 to debut sometime next year, but people excited about the hotter RS variant will likely have to wait until 2024. Audi hasn't said when it plans to reveal the revamped model.

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