2003 Audi A4 problems

• Multitronic 01J (1999-2007)

  · 01J

  It is the generation with the most documented control unit failures, jerking when pulling away and chain wear; it is only worth considering if the gearbox oil change history is verified, there are no stored fault codes and a cold road test shows no jerks or noises.^[2][3]

  With caution

Faults that affect 2003 cars

• Critical severityFrequency: CommonTransmissionWear of the variator chain and conesYes: the variator uses a chain of more than 1,000 links between two pairs of cones that wears with mileage, especially if the oil is not changed regularly. Gebrauchtwagenberater ties the gearbox's reputation to "numerous total failures"; Schaeffler/LuK sells a kit to repair the chain.
• High severityFrequency: CommonElectronicsControl unit (TCU) failure and limp modeYes: the multitronic control unit, especially in the 01J code (up to 2007), is one of its best-documented weak points. Overheating with oil seeping into the control unit causes fault warnings and limp mode and, if ignored, can end up damaging the gearbox itself.
• Medium severityFrequency: CommonClutchJerking and vibration when pulling away from cold (multi-plate clutch)Yes: with no torque converter, the multitronic pulls away using an electronic multi-plate clutch that can jerk or vibrate, especially when cold, if its plates are worn or the oil no longer has the right properties. It is one of the most cited fault symptoms of this gearbox.

• 1.8 T 20v 150 hp (AEB/AGU/ARZ/AUM, 1996-2005)

  150 hp · AEB, AGU, ARZ, AUM

  A German used-car specialist notes that the ignition coils often give trouble on 2001 to 2003 units, and there is a documented case of an unreplaced timing chain tensioner on a 150 hp Passat with 184,000 km.^[6][7]

  With caution

Faults that affect 2003 cars

• High severityFrequency: OccasionalTurboTurbo wear and oil consumptionThe 1.8T turbo can fail over time -cases documented on an Audi TT at 60,000 and 155,000 km- and several sources link it to growing oil consumption in the engine itself. It is not the most cited fault, but it is one of the most expensive when it appears.
• Medium severityFrequency: OccasionalCoolingWater pump failureThe water pump is another documented weak point of the 1.8T: a 180 hp Audi TT had to have it replaced twice, at 110,000 and again at 130,000 km. Coolant leaks "in several places" are also described on a Passat with this engine.Appears at around 110,000 km
• Medium severityFrequency: OccasionalTimingTiming chain tensioner noise and wearAt least one owner documents the timing chain tensioner of this engine left unreplaced, with the resulting chain noise, on a Passat with 184,000 km; another report from a 180 hp Audi TT points to a timing problem at 90,000 km.
• Low severityFrequency: CommonIgnitionIgnition coil failureYes: the ignition coils (one per cylinder) are among the most cited faults of the 1.8T, especially on engines built between 2001 and 2003. They cause hesitation, a rough idle and the engine warning light coming on; usually it is enough to replace the coil of the affected cylinder.
• Low severityFrequency: CommonIntakeAir mass meter (MAF sensor) failureThe air mass meter (MAF sensor) fails fairly often on the 1.8T: on the 150 hp Audi A3 it appears in 3 of the 11 reports collected, and it is also documented on the 180 and 225 hp Audi TT. It causes hesitation and loss of power; it is fixed by replacing the sensor.

• 2.4 V6 30v 136-170 hp (ALW, ARN, ASM, APZ, AMM, AJG, AGA, AML, ALF, APS, ARJ, BDV; 1997-2005)

  136–170 hp · ALW, ARN, ASM, APZ, AMM, AJG, AGA, AML, ALF, APS, ARJ, BDV

  Fiches-auto records 14 reviews of the 170 hp 2.4 V6 A6, with one coil, oil leaks and two catalytic converters replaced at around 190,000 km, and no serious engine faults. These cars are over 20 years old: ask for the invoice for the last belt change (FairGarage gives 120,000 km for the A6 up to 2005).^[10][11]

  With caution

• 3.0 V6 30v 220 hp (ASN, AVK; 2000-2005)

  220 hp · ASN, AVK

  Fiches-auto records 5 reviews of the A6 3.0 V6 (including six coils replaced at around 85,000 km) and 10 of the 220 hp A4 3.0, with three ignition failures and a piston failure at 220,000 km in a convertible. Data is limited: buy with a test drive and belt invoice.^[5][10]

  With caution

Faults that affect 2003 cars

• Medium severityFrequency: OccasionalIgnitionFaulty ignition coilsFiches-auto records failed coils on the A6 2.4 V6 and 3.0 V6 (in one case all six at about 85,000 km) and on the A4 3.0 V6; CarWiki lists the coils among the common faults of petrol A6s. Few cases, with no frequency figures.
• Medium severityFrequency: OccasionalCoolingThermostat and water pump leaking or seizedCarWiki lists leaking coolant pumps and seized thermostats among the causes of faults on A6s, and an owner on fiches-auto changed the thermostat after overheating their 2.8 V6 A6. On the 2.8 the pump is driven by the belt, so it is best changed along with it.
• Low severityFrequency: OccasionalLubricationOil leaks and oil consumptionFiches-auto records oil loss on the A6 2.4 V6 (at around 260,000 km) and high consumption on a 2.8 V6 4Motion Passat at 250,000 km, and a 2006 forum calls oil leaks the biggest problem of the 30v 2.8 V6.

• Critical severityFrequency: OccasionalBrakesRecalls for the rear brake hose and the sealing of the handbrake cableThe A4 B6 had two Audi recalls: in 2002, over a sealing problem in the handbrake cable sheath, and in summer 2003, over a fault in the rear brake hose, according to fiches-auto.fr.Repair: €0
• High severityFrequency: OccasionalSuspensionBreakage of the aluminium front suspension armsOn 1.9 TDI versions, fiches-auto.fr documents fractures of the aluminium front suspension arms from 180,000-210,000 km, a safety fault because it can upset the car's directional control.Appears at around 180,000 km
• Medium severityFrequency: CommonGearbox and clutchEarly wear of the clutch and dual-mass flywheel (diesel)Several owners of 1.9 TDI versions document clutch and dual-mass flywheel failures on fiches-auto.fr between 75,000 and 160,000 km, with combined repairs of up to around €2,000 when both have to be replaced at once.Repair (garage): €1,000–€2,500Appears at around 75,000 km
• Low severityFrequency: CommonElectrical systemBreakage of the electric window regulator mechanismsfiches-auto.fr documents frequent breakages of the electric window regulator mechanism, mainly in the front doors, with testimonials between 90,000 and over 240,000 km and a cost of around €220-250 per mechanism.Repair (garage): €220–€250Appears at around 90,000 km