Episode Details

The EA839 V6 Has Plenty Of Fans, But Reliability Questions Persist

Audi’s EA839 3.0-liter turbo V6 is widely used across the VW Group vehicles. You’ll see it in everything from the Audi S4 and S5 to the SQ5, A6, A7, Q7, Q8, and even some Porsche Cayennes. It has a good reputation for those who want an engine with plenty of tuning potential.

However, this force-inducted V6 mill’s reliability isn’t exactly spotless. Piston failures and oil-guzzling are common, as are scored cylinder walls and cooling-system headaches. The EA839 has even landed in the spotlight over water pump issues, with a lawsuit thrown in for good measure.

Case in point: a 2021 Audi S4 with only 47,000 miles made it through the shop of our favorite engine coroner, I Do Cars. It’s young by most standards, and yet, it has already scored a new engine thanks to a warranty extension.

Hiding a Much Bigger Problem

Everything seemed healthy at first. Spark plugs? Normal. Engine rotation? Smooth as butter. No rod knock, no signs of disaster lurking inside. Even the oil filter was clean, while the timing chains, guides, and tensioners all looked solid. Even the bottom end looked shockingly healthy. Just a bit of sludge in the oil pan, a spotless pickup screen, and barely any wear on the bearings.

However, after one cylinder came off, all three cylinders showed deep scoring. The other side? Pretty much normal. The damage was impossible to miss after pulling the pistons – severe skirt wear and scuffing everywhere, classic signs of piston slap and metal-on-metal drama.

This is a common issue among EA389 V6 engines, according to I Do Cars. The engine probably still ran, but you’d hear a tapping noise and maybe notice the oil level dropping as things got worse.

Interestingly, the car had already gotten a new water pump and thermostat before the engine swap. Makes you wonder if a bit of overheating helped kick off the trouble.

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Can Owners Prevent It?

Some experts think cooling-system gremlins accelerate damage, so swapping out dodgy water pumps and thermostats early might help. Others blame the pistons themselves or tight manufacturing tolerances.

For owners, the best move would be to stay alert. If you hear a rhythmic tapping that speeds up with the engine, spot unexplained oil loss, or catch odd noises from one side, get your car checked ASAP. A quick borescope peek should be able to spot scoring before everything gets ugly.

The good news is that not every EA839 experiences this failure. Many examples have accumulated high