Audi A5

The stock oil pump reduces pressure at idle for better efficiency. This leads to oil starvation at the camshaft adjusters and accelerated wear of bearing surfaces and the timing chain.

Symptoms: Rattling and clattering on cold start or at idle, sporadic fault codes for camshaft adjusters, rough idle

The hydraulic chain tensioners are delicate and prone to hardening from oil coke. A snapped timing chain causes total engine destruction. Also occurs on 2013–2015 model years.

Symptoms: Irregular rattling at warm idle, engine light with timing chain fault codes, in worst case engine failure

The CNCD has two hydraulic chain tensioners that lose pressure at warm, low-viscosity oil and allow the chain to rattle. If neglected, chain jump is a risk.

Symptoms: Irregular rattling at idle after prolonged operation, noise disappears at higher rpm.

The plastic thermostat housing and electric water pump on the EA888 Gen3 can develop leaks. Coolant loss and mild overheating tendency at higher mileages.

Symptoms: Dropping coolant level, coolant smell after driving, temperature gauge above normal range

The EA888 Gen3 (CNCD) also shows elevated oil consumption in some units due to premature coking of the piston ring drain holes. Typical onset at 40,000–70,000 km.

Symptoms: Oil level drops between oil changes, occasional slight blue smoke.

The CVT Multitronic (0AW) tends to catastrophic failures around 100,000 km: juddering when pulling away, extreme rpm fluctuations and loss of reverse gear. Without regular gearbox oil changes, complete failure is likely.

A5 and Q5 models from 2008–2012 with a defective passenger airbag inflator. On deployment, uncontrolled gas pressure can release metal fragments.

Dampers and control arms wear noticeably from around 80,000 km, especially on Sport and S line suspension. A full control arm set costs €2,000–3,000; individual rear dampers around €1,000.

At the transitions between underbody sealant and paint, rust bubbles form on sills and wing bases. Dirt and moisture collect behind underbody covers.

The S tronic dual-clutch gearbox shows premature clutch wear in stop-and-go traffic and when towing. Juddering when pulling away and harsh gearshifts, often fixable by software update.

TÜV inspection reports flag brake hoses on the A5 8T twice as often as the class average. From around 10 years of age rubber hoses become porous.