Explore common problems, estimated repair costs and practical checks for the 2016–2021 Audi A4 3.0 Diesel Automatic B9. Use this guide to help assess a used car, then unlock a personalised report for the exact vehicle you're considering.
Diesel smell from the engine bay, dampness around the top of the engine, or in some cases few warning signs before it is found during inspection.
Use the VIN to confirm recall completion.
£450
Engine warning light, flat acceleration, rough running when warm, or limp mode after town driving.
Drive gently from low revs, then add throttle through the mid-range once the engine is warm.
£1,500
AdBlue warning, emissions warning, restart countdown message, or an engine light with no obvious change in how it drives.
Start the car, let the dash finish its checks, and use the normal menus during the drive.
£950
It can be, but only if the individual car backs it up. For the 2016–2021 Audi A4 3.0 Diesel Automatic B9, treat model-level patterns as viewing priorities and let condition, history and inspection evidence decide.
The problem cards above list the model-level checks for this guide. Read them as priorities for inspection and paperwork review, not proof that every example will have those faults.
Look for evidence, not just assurances: MOT advisories, service history, repair invoices, warning lights, fluid leaks, tyre and brake condition, and how the car behaves on a proper test drive. And of course, look at your personalised Should I Buy This Car? report, outlining a full list of common issues in detail, a personalised road test, a plain-English explanation and a MotorIQ score.
The guide above gives you the model-level pattern. A personalised MotorIQ report checks the registration-specific record and turns it into an ownership view before you commit.
Or enter the vehicle manually