IsItAGoodCar
Reliability Guide

Common Problems with the
2016 Audi A4 Mk5 (B9)

The launch year brought a sharper, more efficient B9 with Virtual Cockpit and updated engines. Water pump and thermostat housing leaks are the primary concern across the range, with LED DRL failures adding to the bill.

What changed for 2016

  • •Launch with 2.0 TFSI and 3.0 TDI engines
  • •New MLB Evo platform
  • •Virtual Cockpit and updated MMI
  • •LED headlights as standard on higher trims

Common MOT watch-outs

  • !Water pump and thermostat housing leaks
  • !LED DRL and indicator failures in headlight units
  • !NOx sensor and AdBlue faults on diesels
4
Known Issues
2
Serious
2
Moderate
0
Minor

All Known Issues

AdBlue SCR System NOx Sensor & Tank Heater Failure

SeriousExhaust & Emissions

On 2.0 TDI and 3.0 TDI diesel models, failing downstream NOx sensors or crystallized AdBlue dosing injectors trigger a persistent dashboard no-restart countdown.

Est. Repair Cost: £450–£1,200
Warning Signs:

"AdBlue: No restart in 650 miles" warning, Engine management light on, Failure to clear after topping up DEF fluid

What to Inspect:
  • Check AdBlue tank filler neck for white crystal deposits
  • Scan for NOx sensor heater circuit fault codes
Verified by IsItAGoodCar Research TeamUpdated

DL382 S tronic Gear Selection / Mechatronic Faults

SeriousGearbox & Transmission

Control or clutch faults can interrupt gear selection. Identify the gearbox code first: this entry applies to the longitudinal DL382 family, not every automatic sold under the same model name.

Warning Signs:

Gearbox warning, Delayed engagement or missing gears

What to Inspect:
  • Test drive from cold and again when warm
  • Check gearbox-specific service invoices and obtain a diagnostic report
Verified by IsItAGoodCar Research TeamUpdated

Water Pump / Thermostat Leaks

ModerateCooling System

Later petrol and diesel engines still suffer coolant leaks from pumps or plastic thermostat housings.

Est. Repair Cost: £350–£750
Warning Signs:

Low coolant warning, Pink residue around front of engine

What to Inspect:
  • Check coolant level cold
  • Look for recent cooling-system repair invoices
Verified by IsItAGoodCar Research TeamUpdated

Front Suspension Multi-Link Upper Control Arm Bushing Wear

ModerateSuspension & Chassis

The five-link front suspension utilizes rubber-metal hydro-bushings on the upper control arms that crack and tear, leading to vague high-speed steering and knocking over potholes.

Est. Repair Cost: £280–£600
Warning Signs:

Knocking noise when braking over uneven surfaces, Uneven front tyre inner edge wear, Steering wander on rutted motorways

What to Inspect:
  • Pry control arms to check for excessive play
  • Inspect rubber boots for oil weeping from hydro-bushings
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 2016 Audi A4 Mk5 (B9)

  • Check coolant level cold and inspect around the pump and housing
  • LED headlight module failures require complete unit replacement — budget £300–£800 per side
  • TDI buyers should verify NOx-sensor and AdBlue history
20152017–2019
Check a 2016 Audi A4 Mk5 (B9) by Registration