Compare Audi A4 diesel engine fault quotes from specialist garages

Since it was founded in 1909, Audi has been at the forefront of automotive innovation. It was the first to conduct crash tests, one of the first to use a dual-clutch gearbox, and in 1921, became the first German manufacturer to make a production car, the Audi Type K, with left-hand drive.

Impressively, Audi is also the most successful carmaker in the history of the World Car Awards, winning 11 titles since 2005 and five World Performance Car Awards as of 2022. Find out whether Audis are expensive to repair in this guide or take a look at how their maintenance costs compare with SEAT and Skoda.

Diesel engine repair jobs are often more expensive than petrol, although diesel cars are more reliable and economical over long distances. The main difference between petrol and diesel engines is that the air is compressed before the fuel is injected in diesels, while in petrols, air and fuel are mixed first, then compressed and ignited.

The most common problems experienced by diesel engines include a clogged diesel particulate filter, stuck EGR valve, turbo failure, worn glow plugs, faulty injectors and low compression. Due to the chemicals and processes involved, some jobs, such as DPF cleaning, may require a diesel engine specialist service.

Many of the above faults have similar symptoms, so the best way to find the specific problem with your vehicle is to use diesel engine diagnostics. If you're experiencing issues with your car, we recommend finding a diesel specialist who can give you expert advice.