The 1.9 TDI engine from Volkswagen is one of the best known and most reliable diesel engines, produced from 1991 to 2010. This engine set the standard for diesel engines of its time and became popular for its durability, economy and excellent performance.
Technical specifications
- Cylinder block material: cast iron
- Engine type: diesel, in-line
- Number of cylinders: 4
- Valves per cylinder: 2
- Piston stroke, mm: 95.5
- Cylinder diameter, mm: 79.5
- Compression ratio: 22.5 and 19.5
- Engine displacement, cc: 1896
Power and torque
The 1.9 TDI engine was offered in several power variants:
- 68 hp at 3,700 rpm
- 75 hp at 4500 rpm
- 90 hp at 4000 rpm
- 90 hp at 3750 rpm
- 110 hp at 4150 rpm
Torque ranged from 140 Nm at 2000-3000 rpm to 235 Nm at 1900 rpm.
Turbocharger
The engine was equipped with various turbochargers including Garrett TB0261, KKK K03, Garrett GT1744V and Garrett GT1749V to improve efficiency and power.
Economy
The 1.9 TDI engine is known for its low fuel consumption. For example, for the Volkswagen Golf 3, the fuel consumption was:
- City: 6.8 l/100 km
- Highway: 4.4 l/100 km
- Mixed cycle: 5.0 l/100 km
Oil and maintenance
Recommended oils for this engine include 5W-30, 5W-40 and 10W-40 and the oil capacity is 4.3 liters. The oil change interval varies from 7500 to 15000 km. Oil consumption can reach up to 500 grams per 1000 km.
Reliability and life
According to the factory, the engine life is not specified, but in practice these engines often exceed 400 thousand kilometers of mileage with proper maintenance.
Application
The 1.9 TDI engine has been installed in various car models, including:
- Volkswagen: Caddy, Golf, Vento/Bora, Passat, Polo, Sharan
- Audi: A3, A4, A6, Cabrio
- Skoda: Octavia
- SEAT: Alhambra, Cordoba, Ibiza, Leon, Toledo
- Ford: Galaxy
Reliability, problems and repair of 1.9 TDI engines
Volkswagen 1.9 turbodiesels appeared in 1991 on VW Passat B3 cars. Here is used cast iron cylinder block with forged crankshaft with a stroke of 95.5 mm and pistons with a diameter of 79.5 mm, which makes it possible to get 1.9 liters of volume.
The first AAZ turbodiesels were fitted with an aluminum single-shaft 8-valve head with pre-chambers. The intake valves were 36mm in diameter, the exhaust valves 31mm, and the valve stem diameter was 8mm. Then came the 1Z, AHU, AFN and other engines that used a direct injection cylinder head. Valve diameter here is 35.9/31.5 mm, valve stem diameter is 7 mm.
The camshaft rotates by means of a toothed timing belt, which must be changed every 60 thousand kilometers.
The first versions were equipped with a mechanical fuel injection system, then the engine was transferred to direct injection. Learn the main differences between the versions below.
Production of 1.9 TDI engines with direct injection continued until 2010, but since 1998 they were replaced by 1.9 TDI with pump injectors.
Modifications of 1.9 TDI engines
- AZZ (1991 – 1998) – a pre-chamber diesel engine with a compression ratio of 22.5 and a mechanical fuel injection system. There were two variants of AAZ: with Garrett TB0261 turbine and with KKK K03. Both variants were without intercooler, boost pressure 0.7 bar. This engine develops 75 hp and 150 Nm of torque.
- 1Z (1991 – 1996) – turbodiesel with direct injection with electronic fuel injection, with other pistons and compression ratio of 19.5. Here there is a turbine Garrett GT1544S with intercooler, and boost pressure is 0.95 bar. Power is increased to 90 hp and torque is 202 Nm at 1900 rpm.
- AHU (1996 – 2001) – replacement of 1Z, which was adjusted to Euro-2 environmental standards.
- AFN (1996 – 1999) – AHU analog with Garrett GT1744V-VNT15 turbine with variable geometry, with other injector atomizers with larger holes and with a different ECU. Power is 110 hp, torque 235 Nm.
- ALE (1997 – 2000) – AHU engine for US environmental standards.
- AGR (1996 – 2005) – transverse variant of AHU diesel engine.
- ALH (1997 – 2010) – same AGR for North American market, but with GT1749V turbine.
- AHH (1997 – 2001) – Same as AFN, but differs in the fuel injector, injectors and Garrett GT1749V turbine. Power is 90 hp, torque 210 Nm.
- AHF (1997 – 2000) – analog ALH with atomizers, as on AFN.
- AVG (1999 – 2001) – renamed AFN.
- ASV (2000 – 2006) – AHF replacement with other pistons.
- ABL (1992 – 2003) – Analogous to AAZ, but with a different fuel injector, Garrett TB0254 turbo, modified oil pan and modified exhaust. It is found only on Volkswagen T4.
Problems and reliability of 1.9 TDI engines
- White smoke in the AAZ. This is usually due to cracks in the cylinder head, which is not uncommon on AAZ. You need to replace the head with a whole one.
- Loss of traction. In almost all cases, the problem lies in the supercharger control valve N75. If this does not help, then it is necessary to carry out diagnostics – the motor is old, there are a lot of options.
These diesel engines are not picky about the quality of fuel, but it is better not to take any risks and not to pour the first hit grease.
Otherwise, these motors are very good and extremely reliable, they have a resource of 400 thousand kilometers and more.
Tuning engines 1.9 TDI (AFN, 1Z, AHU)
Chip tuning
If your engine is not completely ruined and you want to make it go a little faster, you can do chip tuning. Versions with 110 hp are chipped up to 140-150 hp, and the torque will exceed 300 Nm.
Weaker variations at 90 hp on the firmware show 110 hp and 250-260 Nm of torque. Anything else makes no sense – it’s too old a car, there will be no superdynamics anyway.
MOTOR RATING: 4+