The Audi ATD is a 1,781 cc, inline-four petrol engine produced between 2000 and 2005. It belongs to the EA113 engine family and features a DOHC 20-valve configuration with a five-main-bearing crankshaft design. Equipped with Bosch Motronic ME7.5 engine management, it delivered 98 kW (133 PS) and 173 Nm of torque, offering balanced performance and refinement for Audi’s compact and mid-size models during the early 2000s.
Fitted primarily to the Audi A3 (8L), A4 (B5), and TT (8N) models—such as the A3 1.8 and A4 1.8—the ATD was engineered for drivers seeking a blend of responsive throttle response and everyday usability. Its naturally aspirated variant provided smooth power delivery, while select turbocharged versions (designated 1.8T) offered enhanced performance. Emissions compliance was achieved through a three-way catalytic converter and closed-loop lambda control, meeting Euro 3 standards across its production run.
One documented concern is premature wear of the timing belt tensioner and water pump, particularly in higher-mileage applications. This issue, referenced in Audi Technical Service Bulletin 01 09 03, is attributed to material degradation under prolonged thermal cycling. From 2002 onward, Audi introduced revised tensioner components and updated service intervals for coolant and timing belt replacement to improve long-term reliability.
Production years 2000–2005 meet Euro 3 emissions standards (VCA UK Type Approval #VCA/EMS/5681).
The Audi ATD is a 1,781 cc inline-four petrol engine engineered for compact and mid-size applications (2000–2005). It combines DOHC 20-valve architecture with Bosch Motronic ME7.5 engine management to deliver linear power delivery and strong mid-range performance. Designed to meet Euro 3 standards, it balances sporty character with daily drivability.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,781 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-4, DOHC, 20-valve | |
| Aspiration | Naturally aspirated and turbocharged (1.8T variants) | |
| Bore × stroke | 81.0 mm × 86.4 mm | |
| Power output | 98 kW (133 PS) @ 6,000 rpm | |
| Torque | 173 Nm @ 3,200 rpm | |
| Fuel system | Sequential multi-point fuel injection (Bosch Motronic ME7.5) | |
| Emissions standard | Euro 3 | |
| Compression ratio | 11.0:1 (NA), 9.5:1 (turbo) | |
| Cooling system | Water-cooled | |
| Turbocharger | KKK K03 turbo (on 1.8T variants) | |
| Timing system | Timing belt (replaced every 120,000 km or 5 years) | |
| Oil type | SAE 5W-40, VW 502 00 specification | |
| Dry weight | 135 kg |
The ATD engine delivers responsive performance but requires strict adherence to 5-year/120,000 km timing belt replacement intervals to prevent catastrophic interference engine damage. VW 502 00 (5W-40) oil is essential for turbo and bearing protection. Extended idling or aggressive warm-up routines should be avoided to reduce turbo bearing stress. The ME7.5 ECU is flashable for mild tuning, but intake and exhaust restrictions limit peak airflow. Pre-2002 models are prone to tensioner failure; post-TSB revisions include upgraded water pump and tensioner assemblies. Regular inspection of vacuum lines and N75 boost control solenoid is advised to maintain driveability.
Oil Specs: Requires VW 502 00 specification (Audi SIB 01 09 03). Compatible with ACEA A3/B3 standards.
Emissions: Euro 3 certification applies to all ATD models (2000–2005) (VCA Type Approval #VCA/EMS/5681).
Power Ratings: Measured under DIN 70020 standards. Output varies slightly between manual and automatic transmissions (Audi TIS Doc. A18260).
Audi Technical Information System (TIS): Docs A18260, A18261, SIB 01 09 03
VCA Type Approval Database (VCA/EMS/5681)
SAE International: J1349 Engine Power Certification Standards
The Audi ATD was used across Audi's 8L/B5/8N platforms with longitudinal mounting and shared architecture with Volkswagen Group derivatives. This engine received platform-specific adaptations—different intake manifolds on the A3 versus TT—and from 2002 the facelifted A4 B5.5 adopted revised engine mounts and updated ECU calibrations, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front face of the cylinder block, near the timing belt cover (Audi TIS A18260). The 7th digit of the VIN indicates engine type ('D' for ATD in most European markets). Naturally aspirated models have a silver intake manifold; turbocharged variants feature a black plastic manifold with intercooler piping. Critical differentiation from similar EA113 engines: ATD uses a 20-valve head with ME7.5 ECU (round diagnostic connector), while non-turbo 1.8L 20V engines may use earlier management systems. Service parts require model-year verification—timing kits for pre-2002 models are incompatible with post-TSB units due to tensioner redesign (Audi TSB 01 09 03).
The ATD's primary reliability risk is timing belt system failure on pre-2002 builds, with elevated incidence in vehicles with extended service intervals. Internal Audi service reports from 2004 indicated a significant number of interference engine failures due to belt/tensioner wear, while VCA MOT data shows increased catalytic converter degradation in high-mileage urban-driven units. Infrequent servicing and use of non-spec oil increase turbo and bearing wear, making timing maintenance and fluid adherence critical.
Analysis derived from Audi technical bulletins (2000-2005) and UK DVSA failure statistics (2000-2010). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about AUDI ATD.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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