CarValidator

40 / 45 TFSI (2.0 EA888 / 3.0 EA839)

20182024 · petrol · 1984cc · 245hp

Engine codes: DKNA, DLZA, DEWA

Maint. Sensitive

Reliability, common problems and owner reviews for the Audi A6 C8 40 / 45 TFSI (2.0 EA888 / 3.0 EA839). Check this before you buy used.

The petrols span the 2.0 TFSI (40/45 TFSI, EA888 Gen3 with 48V mild-hybrid — shared with the A4/A5/Q5) and the smooth 3.0 V6 TFSI (55 TFSI, EA839). The 2.0 EA888 Gen3 is robust (chain-driven, the Gen2 oil-burn long resolved) with the usual modern cautions — chain-tensioner, PCV, DI carbon — plus the 48V mild-hybrid system; the V6 adds its own complexity and cost. Both pair with the S tronic/tiptronic and quattro. A documented car with a healthy chain is dependable and refined. Buy on oil, chain and (48V/gearbox) service history.

Same engine, other cars

This is the same physical engine (DKNA) sold under different names across brands. Reliability is broadly shared — cross-check these:

Known Issues

Chain tensioner / PCV / carbonrecurring

EA888 chain tensioner attention; PCV faults; DI intake carbon over time.

Fix / Workaround: Revised tensioner; PCV; decarbon.

Repair cost: €200–€1500

Typically appears after: 130,000 km

48V mild-hybrid / S tronicrecurring

48V belt-starter system; dual-clutch fluid service.

Fix / Workaround: Diagnose 48V; S tronic fluid service.

Repair cost: €200–€1800

Typically appears after: 140,000 km

Mileage Thresholds

After 180,000 km: Chain + DCT window.

Pre-Purchase Checklist

  • 2.0 EA888 Gen3 is robust
  • Same EA888 as A4 / A5 / Q5
  • Oil + chain + DCT history

Frequently asked questions

Is the Audi A6 C8 40 / 45 TFSI (2.0 EA888 / 3.0 EA839) reliable?

Maint. Sensitive — The petrols span the 2.0 TFSI (40/45 TFSI, EA888 Gen3 with 48V mild-hybrid — shared with the A4/A5/Q5) and the smooth 3.0 V6 TFSI (55 TFSI, EA839). The 2.0 EA888 Gen3 is robust (chain-driven, the Gen2 oil-burn long resolved) with the usual modern cautions — chain-tensioner, PCV, DI carbon — plus the 48V mild-hybrid system; the V6 adds its own complexity and cost. Both pair with the S tronic/tiptronic and quattro. A documented car with a healthy chain is dependable and refined. Buy on oil, chain and (48V/gearbox) service history.

What are the common problems and reviews for the Audi A6 C8 40 / 45 TFSI (2.0 EA888 / 3.0 EA839)?

The most commonly reported problems: Chain tensioner / PCV / carbon, 48V mild-hybrid / S tronic.

Is a used Audi A6 C8 40 / 45 TFSI (2.0 EA888 / 3.0 EA839) worth buying?

Fine if serviced correctly — but it punishes neglect hard. History and the right consumables matter.