Audi A4
Most powerful V6 naturally aspirated engine in the B5 with 142 kW. Available only with all-wheel drive. Timing chain — watch the tensioners. Refined running.
Smooth multi-cylinder — effortless touring
193 hp 2.8L with pleasant refinement. Relaxed cruising, no sporting ambitions. Budget for the known weak points.
Engine Weaknesses 5
The Multitronic CVT paired with the V6 APR in the A6 is not well-suited to the high torque figures. Neglecting the oil change leads to slipping and ultimately gearbox failure.
Symptoms: Poor acceleration despite high engine rpm, juddering on pull-away, gearbox slipping, gearbox warning light
The 2.8 V6 APR has a timing belt whose replacement interval (90,000–120,000 km) is often missed on used cars. Belt failure on this interference engine causes total engine destruction.
Symptoms: No warning on belt snap; checking the service history is the only precaution; no symptoms on correctly maintained examples
The 2.8 V6 APR uses older soft gaskets rather than modern multi-layer steel gaskets. Thermal cycling and geometric tolerances on the bolt angles can cause the gasket to fail in the V-bank area.
Symptoms: Oil in the V-bank between cylinder rows, coolant loss, white smoke, engine overheating when gasket fails
The water pump on the V6 APR should be replaced together with the timing belt kit. A leaking pump causes coolant loss and overheating damage, especially on poorly maintained examples.
Symptoms: Coolant loss, temperature rise during driving, coolant puddle under the car, heating cools down with heavy loss
The valve stem seals on the V6 APR wear and allow oil into the combustion chamber. Typical consumption is 0.5–1 L/1,000 km at high mileage; blue smoke especially on cold start.
Symptoms: Blue smoke on cold start and after a long stand, oil consumption with no visible external leaks, carbon deposits on spark plugs
Vehicle Weaknesses 5
Despite a fully galvanised body, the A4 B5 rusts at typical spots: door lower edges (behind door strips), bonnet fold at the sides, boot lid, lock panel and roof folds. Rust in roof rails is a well-known long-term issue on many A4 B5s.
The lower straight control arms and their rubber bushings are worn out on almost all older A4 B5s. Characteristic squeaking and knocking noises over bumps. Replacement parts are available cheaply (Lemförder ~€35 each).
Rust-like particles in the A4 B5 coolant reservoir indicate a clogging heater core. The symptom is poor heating performance. At higher mileages, old coolant hoses and the heater core itself must be inspected.
The A4 B5 AC compressor shows first signs of weakness from as little as 60,000 km. Common symptoms are loud noises when the AC is switched on or complete cooling failure. Quality replacement compressors are available.
With increasing age the A4 B5 frequently experiences window regulator motor failure, door lock motor failure, mirror adjustment motor failure and immobiliser transponder failure. These wear issues are typical for a 25+ year old vehicle.