VW Fox
Economical three-cylinder diesel with unit injector. Known for EGR problems in short-trip use. Robust engine with regular maintenance and motorway driving.
Frugal Diesel Three-Cylinder
70 hp and decent torque — the Fox feels noticeably stronger with this than with the 1.2 petrol. Ideal for commuters.
Engine Weaknesses 4
The fuel lift pump fails on early production vehicles. The vehicle won't start or cuts out under load.
Symptoms: Engine won't start after extended standing. No pump priming sound before engine start. Vehicle cuts out under load or runs very roughly.
The 1.4 FSI BNM in the Polo 9N shares the cam follower problem common to all FSI engines. The high-pressure pump follower wears and must be regularly inspected. When it fails, fuel pressure drops.
Symptoms: Fault message implausible pressure signal, fuel pressure too low, power loss up to approx. 50 km/h
The direct injection injectors of the 1.4 FSI BNM leak or fail and cause rough running and misfires. VW recommended prophylactic replacement of all 4 injectors when one is diagnosed. Replacement requires removal of the lower intake manifold.
Symptoms: Severe rough running and hesitation, especially at idle. Engine light with misfire fault codes (cylinder code), noticeable power loss when accelerating.
The EGR valve is prone to heavy soot build-up, especially with short-trip driving. Leads to power loss and increased fuel consumption.
Symptoms: Power loss at mid-range rpm, black smoke on acceleration, increased fuel consumption, engine warning light with EGR fault code.
Vehicle Weaknesses 10
Sills and rear wheel arches rust through prematurely, especially on the underside of the sills behind the front wheels. Rusted-through sills cause MOT failure.
Control arm bushings and ball joints wear relatively early. Flagged at MOT and leads to suspension clunks and an unsettled straight-line drive.
The thermostat sticks in the open or closed position. When stuck closed the engine overheats; when stuck open it never reaches operating temperature.
The hydraulic power steering pump often fails after a cold start and only returns to normal after a few kilometres. Replacement is comparatively costly.
Window regulators fail through broken cables or defective motors. The window can then no longer be closed. Driver and passenger door are most commonly affected.
Front wheel bearings wear and announce themselves with a characteristic drone that gets louder with increasing speed.
Exterior door handles become brittle from UV exposure and frequent use and break off. The plastic housing fails at the pivot point, most often on the driver's side.
The tailgate lock jams especially in cold weather or through contamination. The locking mechanism has insufficient return force and fails in winter.
ESP warning light illuminates without an actual fault. Often caused by defective sensors or ECU software errors. Not a safety risk but troublesome at MOT.
Rear drum brakes and handbrake mechanism tend to seize, especially after extended standing periods. Brake pads corrode onto the brake drum.