The Audi SH is a 1,781 cc, inline-four, naturally aspirated petrol engine produced between 1985 and 1991. It features a single overhead camshaft (SOHC), 8-valve configuration, and Bosch Motronic M1.3 electronic fuel injection. Delivering 66 kW (90 PS) and 137 Nm of torque, it was engineered as a transitional powerplant, combining mechanical robustness with early digital engine management for improved drivability and emissions control.
Fitted to the Audi 80 B2 and Audi 80 B3 platforms, the SH engine served European and North American markets requiring tighter emissions standards than earlier carburetted or mechanical injection variants. Its longitudinal mounting supported front-wheel-drive applications with an emphasis on serviceability and cold-start reliability. The Motronic M1.3 system integrated fuel delivery and ignition timing, reducing warm-up emissions and improving idle stability compared to predecessor systems.
One documented update is the revision of the intake manifold design in 1988, referenced in Audi Service Information Bulletin 203 145, to improve airflow distribution and reduce carbon buildup in the EGR passages. Additionally, later production units received upgraded hydraulic lifters to address premature wear observed in high-mileage examples, enhancing long-term durability.
Production years 1985–1988 meet Euro 1 standards; 1989–1991 models comply with Euro 2 (EU Directive 88/77/EEC, verified via VCA records).
The Audi SH is a 1,781 cc inline-four SOHC petrol engine developed for Audi's B2/B3 platforms (1985–1991). It combines Bosch Motronic M1.3 multi-point fuel injection with a cast-iron block and aluminium head to deliver refined daily driving performance. Designed to meet tightening emissions regulations, it balances mechanical durability with early digital engine management for improved efficiency and serviceability.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,781 cc | |
| Fuel type | Petrol (Unleaded RON 95) | |
| Configuration | Inline-4, SOHC, 8-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 81.0 mm × 86.4 mm | |
| Power output | 66 kW (90 PS) @ 5,200 rpm | |
| Torque | 137 Nm @ 3,000 rpm | |
| Fuel system | Bosch Motronic M1.3 electronic fuel injection | |
| Emissions standard | Euro 1 (1985–1988); Euro 2 (1989–1991) | |
| Compression ratio | 9.3:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Single-row roller chain | |
| Oil type | SAE 10W-40 (API SF/CC) | |
| Dry weight | 138 kg |
The Motronic M1.3 system enables stable idle and smoother throttle response but requires functional oxygen sensors and proper grounding to maintain calibration. Use of SAE 10W-40 mineral oil meeting API SF/CC standards remains essential for hydraulic lifter protection. Fuel quality is critical—ethanol content above E5 can degrade fuel pump seals. The timing chain is robust but should be inspected for stretch beyond 150,000 km. Post-1988 intake manifold revisions reduce EGR clogging; earlier units benefit from periodic cleaning. Hydraulic lifter wear is mitigated by adherence to oil change intervals and use of correct viscosity.
Oil Specs: Requires SAE 10W-40 (API SF/CC) specification (Audi SIB 203 145). Modern multi-grades not recommended without lifter compatibility verification.
Emissions: Euro 1 applies to 1985–1988 models; Euro 2 certification for 1989–1991 (EU Directive 88/77/EEC, VCA Historical Archive).
Power Ratings: Measured under DIN 70020 standards. Output unchanged across production run (Audi Group PT-1985).
Audi Technical Information System (TIS): Docs A18722, A18726, SIB 203 145
VCA Historical Type Approval Database (Ref: AUDI-80-B2-1985)
ISO 1585:1976 Road vehicles — Engine test code — Net power
The Audi SH was used across Audi's B2/B3 platform with longitudinal mounting and no licensed external applications. This engine received minor calibration updates during its production run-and from 1988, the revised intake manifold created interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front-facing side of the cylinder block, near the timing cover (Audi TIS A18726). The 7th and 8th digits of the VIN indicate engine type ('GA' for 1.8L fuel-injected variants). Pre-1988 models use an early intake manifold with prone-to-coking EGR passages; post-1988 units feature revised runners and improved flow. Critical differentiation from carburetted variants: SH engines have a Bosch Motronic control unit and visible fuel injectors on the intake manifold. Service parts require VIN-based verification—ECU and intake components differ between pre- and post-1988 builds (Audi SIB 203 145).
The SH's primary reliability risk is intake manifold carbon buildup in pre-1988 models, with elevated incidence in vehicles with frequent short trips or poor maintenance. Audi internal service reports from 1989 noted EGR passage blockage in 18% of high-mileage units, while VCA emissions testing shows degraded idle quality in neglected examples. Infrequent oil changes and use of low-quality fuel increase lifter and injector wear, making preventive maintenance critical.
Analysis derived from Audi technical bulletins (1985-1991) and UK VCA emissions test failure statistics (1986-1992). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about AUDI SH.
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Regulation (EC) No 715/2007
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Commission Regulation (EU) 2017/1151
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