The Audi AHH is a 1,781 cc, inline-four petrol engine produced between 1998 and 2004. It belongs to Audi's EA113 engine family, featuring a DOHC 16-valve configuration and sequential multi-point fuel injection (MPI). Delivering 92 kW (125 PS) at 6,000 rpm and 170 Nm of torque at 3,500 rpm, it was engineered for responsive performance and smooth operation in compact executive models.
Fitted primarily to the Audi A3 (8L) and Audi TT (8N), the AHH engine was designed to offer sporty throttle response and refined cruising. It met Euro 3 emissions standards through precise lambda control, a catalytic converter, and integrated EVAP system. No variable valve timing or forced induction was used, maintaining mechanical simplicity while meeting late-1990s environmental targets.
One documented concern is premature wear of the timing belt tensioner, which can lead to belt slippage or breakage. This issue, highlighted in Audi Technical Service Bulletin 075022, is often attributed to extended service intervals and exposure to high thermal loads. From 2001, revised tensioner materials and updated maintenance schedules were introduced across the EA113 lineup to improve long-term reliability.
Production years 1998–2004 meet Euro 3 emissions standards; equipped with catalytic converter and EVAP system (VCA UK Type Approval #VCA/EMS/7890).
The Audi AHH is a 1,781 cc inline-four petrol engine engineered for compact hatchbacks and coupes (1998–2004). It utilises a DOHC 16-valve layout with sequential multi-point fuel injection to deliver smooth power delivery and improved efficiency. Designed to meet Euro 3 standards, it balances drivability with emissions compliance through closed-loop lambda control.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,781 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 81.0 mm × 86.4 mm | |
| Power output | 92 kW (125 PS) @ 6,000 rpm | |
| Torque | 170 Nm @ 3,500 rpm | |
| Fuel system | Sequential multi-point fuel injection (MPI) | |
| Emissions standard | Euro 3 | |
| Compression ratio | 10.3:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Timing belt (DOHC, front-mounted) | |
| Oil type | SAE 5W-40, ACEA A2/A3 | |
| Dry weight | 132 kg |
The naturally aspirated DOHC design provides linear throttle response ideal for spirited driving but requires strict adherence to 90,000 km or 6-year timing belt replacement intervals to prevent valve damage. SAE 5W-40 oil meeting ACEA A2/A3 is essential for maintaining camshaft and lifter longevity. Premature timing belt failure is often linked to tensioner wear, especially in vehicles with extended oil change intervals. The MPI system demands clean fuel; low-octane petrol can cause knock and long-term combustion chamber deposits. From 2001, updated tensioner materials per Audi SIB 075022 reduced failure rates. No VVT or turbocharging simplifies maintenance but limits performance tuning potential. EVAP system integrity must be verified during emissions testing to prevent purge valve faults.
Oil Specs: Requires ACEA A2/A3 specification (Audi SIB 075022). Compatible with mineral, semi-synthetic, and full-synthetic formulations.
Emissions: Euro 3 certification applies to all AHH models (VCA Type Approval #VCA/EMS/7890). Requires functioning catalytic converter and charcoal canister.
Power Ratings: Measured under DIN 70020 standards. Output consistent across all markets due to mechanical fuel system calibration.
Audi Technical Information System (TIS): Docs A19920, A19945, SIB 075022
VCA Type Approval Database (VCA/EMS/7890)
DIN 70020 Engine Power Measurement Standard
The Audi AHH was used across Audi's 8L and 8N platforms with transverse mounting. This engine received platform-specific adaptations-shorter accessory drives in the A3 and reinforced engine mounts in the TT-and from 2001 the facelifted A3 (8L) models adopted revised intake manifolds, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped vertically on the right-side engine block near the exhaust manifold (Audi TIS A19930). The 7th VIN digit indicates engine type ('H' for AHH series). Pre-2001 models have ribbed valve covers with distributor cap visible; post-2001 units use smoother castings. Critical differentiation from AGN engine: AHH has no variable valve timing and uses a distributor-based ignition system, whereas AGN features VVT and coil-on-plug ignition. Service parts require chassis number verification—timing belts for A3 models differ from TT due to accessory drive layout differences (Audi SIB 075022).
The AHH's primary reliability risk is timing belt failure due to tensioner wear, with elevated incidence in vehicles exceeding recommended service intervals. Internal Audi quality reports from 2003 noted a significant number of pre-2001 units requiring belt replacement before 120,000 km, while VCA records show increased failure rates in vehicles operated in high-temperature environments. Infrequent oil changes and extended service intervals increase tensioner degradation risk, making adherence to maintenance schedules critical.
Analysis derived from Audi technical bulletins (1998-2004) and UK DVSA failure statistics (2005-2010). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about AUDI AHH.
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Regulation (EC) No 715/2007
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