Afn 1.9 tdi engine operating principle. Volkswagen Diesel Engines - Buyer's Guide. Typical problems: owners' opinion
The 1.9 TDI (ALH) engine was produced from approximately 1997 to 2006. It can be found on VAG cars belonging to the budget segments. In particular, the 1.9 TDI (ALH) engine was widely used in the first generations of Skoda Octavia and Seat Leon. It can also be found under the hoods of Volkswagen Golf 4, Bora/Jetta, New Beetle, Caddy, Polo and even Ford Galaxy and Audi A3. This power unit develops 90 hp. at 3750 rpm and 210 Nm at 1900 rpm.
The fuel system of the 1.9 TDI engine (ALH) is based on a distribution injection pump. There is no question of any pump injectors and, especially, Common Rail.
1.9 TDI (ALH) - it's simple and reliable
This engine is valued for its simple and reliable design “originally from the 1990s”. Only, unlike its ancestors, this engine was equipped with a turbine with variable guide vane geometry and an EGR system.
The 1.9 TDI (ALH) engine also has simpler modification, indicated by the index AGR. This option develops the same torque and power (90 hp), only its peak occurs at 4000 rpm. AGR motor conditionally even more budget-friendly: initially it was equipped with a simple single-mass flywheel, whereas ALH was always dual-mass. By the way, the AGR began to be equipped with a dual-mass flywheel, starting with the 100,001st copy.
The engines also differ in turbines. If the ALH has a turbine with advanced control and variable geometry, then the AGR turbine is simpler, without geometry and is controlled through a bypass valve. Notorious the boost control valve (N75) is present on both engines. Only on ALH it controls the vacuum drive-actuator of the turbine geometry, on AGR it controls the pressure that opens the bypass valve.
The 1.9 TDI (ALH) engine can be purchased at a favorable price from the MotorLand company with a guarantee.
Engine problems 1.9TDI (ALH), or how to kill one of the most resourceful engines
Frank design problems or defects in the 1.9 TDI engine (ALH and AGR) generally not. All problems of these engines arise for simple reasons: due to the lack of normal maintenance and general neglect of the power unit. To extend the service life (and the service life of this motor easily exceeds 500,000 km) of the ALH engine, you need to periodically:
- carry out computer diagnostics;
- check the performance of the injection pump and injectors;
- clean the intake manifold of carbon deposits, soot and oily deposits;
- monitor the condition of the turbine.
In general, almost all the troubles of the 1.9 TDI (ALH) engine lie in the EGR system and turbine.
1.9 TDI (ALH) engine does not start
Often the 1.9 TDI (ALH) engine refuses to start. The first step is to check the flap located in the EGR valve. This valve (usually called a throttle valve, although in fact it is designed to restrict the flow of air to add exhaust gases entering through the EGR valve) is actually designed to ensure that the diesel engine shuts down smoothly after turning off the ignition: it closes the intake manifold, in the absence of inflow air, the engine stops smoothly.
If the throttle is stuck in the closed position due to soot, the engine will not start. The stem of this damper is easily accessible, in most cases it can be opened manually by simply pressing on the stem. If the engine starts, the entire EGR valve must be removed and cleaned of carbon deposits.
1.9 TDI (ALH) engine does not develop power
Often the 1.9 TDI (ALH) engine stops pulling and developing normal power. This usually happens suddenly after accelerating to 130 km/h or above. After reducing speed, the engine stops developing normal power and responds sluggishly to the accelerator. Such symptoms indicate that the “geometry” of the turbine is “stuck” in the position of the minimum angle of attack of the blades, which exactly corresponds to the high load mode (when there is enough exhaust gas flow to the turbine wheel to ensure high turbine performance). There are several reasons why the geometry mechanism freezes:
- you need to check its functionality. This is done with the engine running at idle speed. You need to disconnect the vacuum tube from the actuator (pneumatic valve, “fungus”) of the geometry drive, and then put it in place. In this case, the actuator rod should go down when disconnecting the tube, and after putting on the tube it should smoothly go up. If nothing like this happens: the rod does not move or moves jerkily, then the geometry mechanism is worn out. It is best to send the turbine for restoration.
- if the “geometry” works normally, then you need to move on to computer diagnostics and run a check of the “basic settings” of the turbine control. The system will check the functionality of the boost control valve (valve N75), which controls the same pneumatic valve. If the actuator rod does not move, then the fault should be looked for in the N75 valve or in the hoses. There are three of these tubes: vacuum, “atmospheric” and turbine control (it is connected directly to the pneumatic valve). All tubes tend to fray. If there is a vacuum leak, then the turbine geometry does not move to the position of the maximum angle of attack of the guide vanes and the turbine “underblowing” occurs. If there is a leak in the atmospheric tube, then the “geometry” of the turbine cannot go into the minimum angle of attack mode, and as a result, the turbine “overblown” occurs, which is felt during acceleration and high engine loads. In this case, the turbine control system, in the event of high deviations from the normal pressure in the intake manifold, commands valve N75 to move the turbine blades to the minimum angle of attack position, thereby reducing the intake pressure. Engine power drops. If you turn off the engine and start it again, the emergency turbine control mode is disabled. But only until the boost pressure again deviates from the norm.
- A decrease in engine power occurs when the intake manifold loses its tightness. Usually a hole is formed in the intercooler through which air is released.
The 1.9 TDI (ALH) engine produces excess power
But the opposite situation, when the 1.9 TDI (ALH) engine suddenly starts to drive very quickly, usually ends in serious trouble. But first, there are two things to note about “driving fast”:
- The turbine geometry can suddenly become stuck in a position that produces high boost pressure.
- after installing a new, working turbine, the engine can return to its original boost and power parameters.
In the situations described above, the following occurs: normal or high flow of air compressed by the turbine blows oil out of the intercooler, which had been accumulating there for months.
Where does the oil in the intercooler come from? As a rule, all turbodiesels “send” some portions of oil into the intake. But an excess amount of oil in the intake and in the intercooler in particular appears there due to wear of the turbine cartridge. And the engine can run on this oil, but not for long. The oil, picked up by a fast flow of air compressed by the turbine, enters the combustion chambers, and the engine speed increases sharply, as if at maximum fuel supply. But at the same time, there is simply no limiter for the supply of this alternative fuel, and the oil literally flows into the cylinders and burns there.
At the same time, the speed of the motor increases to the limit. The engine is either destroyed(with connecting rods coming off and so on) or jams due to overheating. There are times when so much oil enters the cylinders that water hammer occurs. Actually, “overrun” is the only reason why the 1.9 TDI (ALH) engine “dies”. There are known cases when the engine went into disarray due to a new and fully working turbine, which was installed without first cleaning the intake manifold.
Serious damage to the 1.9 TDI (ALH) engine is rarely caused pouring injectors or faulty fuel injection pump. Due to excess fuel supply to the cylinders pistons burn out. However, a problem with fuel supply can be noticed in advance by increased consumption and problems with starting the engine.
In general, the 1.9 TDI (ALH) engine turned out to be relatively simple and reliable. Problems with it arise due to age, mileage, savings on maintenance, diagnostics and ignoring incipient problems with the turbine. If this engine still fails, you can buy a 1.9 TDI (ALH) unit for Skoda Octavia, Volkswagen Golf and other cars from the MotorLand company.
Engine 1.9 TDI (AFN, 1Z, AAZ, AHU)
Characteristics of 1.9 TDI engines
| Production | Volkswagen |
| Engine make | 1.9 TDI |
| Years of manufacture | 1991-2010 |
| Cylinder block material | cast iron |
| engine's type | diesel |
| Configuration | in-line |
| Number of cylinders | 4 |
| Valves per cylinder | 2 |
| Piston stroke, mm | 95.5 |
| Cylinder diameter, mm | 79.5 |
| Compression ratio | 22.5 19.5 |
| Engine capacity, cc | 1896 |
| Engine power, hp/rpm | 68/3700 75/4500 90/4000 90/4000 90/3750 110/4150 |
| Torque, Nm/rpm | 140/2000-3000 150/2400-3400 202/1900 210/1900 210/1900 235/1900 |
| Environmental standards | - |
| Turbocharger | Garrett TB0261 KKK K03 Garrett GT1744V Garrett GT1749V |
| Engine weight, kg | ~200 |
| Fuel consumption, l/100 km (for Golf 3) - city - track - mixed. |
6.8 4.4 5.0 |
| Oil consumption, g/1000 km | up to 500 |
| Engine oil | 5W-30 5W-40 10W-40 |
| How much oil is in the engine, l | 4.3 |
| Oil change carried out, km | 15000 (better 7500) |
| Engine operating temperature, degrees. | - |
| Engine life, thousand km - according to the plant - on practice |
- 400+ |
| Tuning, hp - potential - without loss of resource |
- - |
| The engine was installed | VW Caddy Volkswagen Golf VW Vento/Bora Volkswagen Passat VW Polo Audi A3 Audi A4 Audi A6 Skoda Octavia Audi Cabrio Volkswagen Sharan SEAT Alhambra SEAT Cordoba SEAT Ibiza SEAT Leon SEAT Toledo Ford Galaxy |
Reliability, problems and repair of 1.9 TDI engines
Volkswagen 1.9 turbodiesels appeared in 1991 on the VW Passat B3. A cast-iron cylinder block with a forged crankshaft with a stroke of 95.5 mm and pistons with a diameter of 79.5 mm is used here, which makes it possible to obtain 1.9 liters of volume.
The first AAZ turbodiesels had an aluminum single-shaft 8-valve head with pre-chambers. The diameter of the intake valves was 36 mm, the exhaust valves were 31 mm, and the diameter of the valve stem was 8 mm. Then the 1Z, AHU, AFN and other engines appeared, which used a cylinder head with direct injection. The valve diameter here is 35.9/31.5 mm, the stem diameter is 7 mm.
The camshaft rotates via a timing belt, which needs to be changed every 60 thousand km.
The first versions were equipped with a mechanical injection pump, then the engine was switched to direct injection. You can find out the main differences between the versions below.
The 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
1. AZZ (1991 - 1998) - pre-chamber diesel with a compression ratio of 22.5 and a mechanical injection pump. There were two versions of the AAZ: with a Garrett TB0261 turbine and with a KKK K03. Both options were without an intercooler, the boost pressure was 0.7 bar. This internal combustion engine develops 75 hp. and 150 Nm of torque.
2. 1Z (1991 - 1996) - direct injection turbodiesel with electronic injection pump, with different pistons and a compression ratio of 19.5. There is a Garrett GT1544S turbine with an intercooler, and the boost pressure is 0.95 bar. Power is increased to 90 hp, and torque is 202 Nm at 1900 rpm.
3. AHU (1996 - 2001) - replacement for 1Z, which was adjusted to Euro-2 environmental standards.
4. AFN (1996 - 1999) - an analogue of the AHU with a Garrett GT1744V-VNT15 variable geometry turbine, with different injector nozzles with large holes and with a different ECU. Power 110 hp torque 235 Nm.
5. ALE (1997 - 2000) - AHU engine for US environmental standards.
6. AGR (1996 - 2005) - transverse version of the AHU diesel engine.
7. ALH (1997 - 2010) - the same AGR for the North American market, but with a GT1749V turbine.
8. AHH (1997 - 2001) - analogous to AFN, but differs in fuel injection pump, injectors and Garrett GT1749V turbine. Power 90 hp, torque 210 Nm.
9. AHF (1997 - 2000) - an analogue of ALH with sprayers, like on AFN.
10. AVG (1999 - 2001) - renamed AFN.
11. ASV (2000 - 2006) - replacement of AHF with different pistons.
12. ABL (1992 - 2003) - analogous to AAZ, but with a different injection pump, with a Garrett TB0254 turbine, with a modified sump and a modified exhaust. Found only on Volkswagen T4.
Problems and reliability of 1.9 TDI engines
1. White smoke from 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.
2. Loss of traction. In almost all cases, the problem lies in the N75 boost control valve. If this does not help, then you need to carry out diagnostics - the motor is old, there are a lot of options.
These diesel engines are not particularly picky about fuel quality, but it’s better not to take risks and not pour the first liquid you come across.
Otherwise, these engines are very good and extremely reliable, with a service life of 400 thousand km or more.
Tuning 1.9 TDI engines (AFN, 1Z, AHU)
Chip tuning
If your engine has not yet completely fallen apart and you want to make it go a little faster, then you can do chip tuning. 110 hp versions chipped up to 140-150 hp, while the torque will exceed 300 Nm.
Weaker variations of 90 hp. The firmware shows 110 hp. and 250-260 Nm of torque. Everything else makes no sense - the car is too old, it won’t be super-dynamic anyway.
The German automaker Audi has always been famous for its powerful and economical engines, which combined excellent efficiency and provided the car with proper dynamics. Particularly popular are Audi diesel engines, which at one time had record-breaking efficiency figures. One of the most common and popular is the Audi 1.9 D engine, which was installed on cars from 1989 to 1993.
Specifications
Audi 1.9 D engines under the symbol 1Y have the following characteristics:
| OPTIONS | MEANING |
|---|---|
| Years of manufacture | 1989 - 1991 |
| Weight | N. d. |
| Cylinder block material | cast iron |
| Motor power system | injection |
| Type of cylinder arrangement | In a row |
| Engine displacement | 1.9 liters |
| Engine power | 67 l. With. |
| Number of cylinders | Four |
| Number of valves | Two |
| Piston stroke | 95.5 millimeters |
| Cylinder diameter | 79 millimeters |
| Compression ratio | 19 |
| Torque, Nm/rpm | 127/2200 |
| Environmental standards | n. d. |
| Fuel | diesel |
| Fuel consumption | 5.6 l/100 km |
| Oil | 5W-30 |
| Oil volume in crankcase | 4.30 liters |
| When replacing, pour | 4 liters |
| Oil change is carried out | Every 10 thousand km |
| Motor life | |
| - according to the plant | 250 |
| - on practice | 500 |
The engine is installed on the Volkswagen Passat B3, Volkswagen Golf 2 and Audi 80.
Description
This fairly simple naturally aspirated diesel engine has a power of 67 horsepower, which is enough for such a small Audi 80 car.
At the same time, fuel consumption in the combined cycle was at one time one of the best among popular cars.
A car with an Audi engine consumed an average of 5.6 liters of diesel fuel. At the same time, due to the excellent traction from the very bottom, the car had good dynamics, and the car owner did not experience any lack of traction in a wide speed range.
The engine has indirect fuel injection and an OHC gas distribution system, which improved power characteristics and eliminated pronounced detonation and vibration at idle.
Note that there is no supercharging, which significantly increases the service life of Audi engines. However, Audi and most other automakers subsequently abandoned the idea of producing naturally aspirated diesel engines. However, according to reviews from car owners, this car with an atmospheric diesel power unit does not have any lack of power and traction. With a 1.9D engine, the Audi 80 accelerates to hundreds in 16 seconds, which is a good indicator for that time.
If we talk about the reliability of the Audi engine, then all car owners, without exception, speak positively about this engine. Subsequently, when developing the next generation of diesel engines, Audi used most of the components and developments from this model, actually equipping this engine with a turbine and changing a number of components. It is not uncommon to have Audi 80s with a 1.9 D engine that have run 500-800 thousand kilometers without major repairs. And with a high-quality overhaul, Audi engines can last up to a million kilometers.
The cast iron alloy used is highly durable and resistant to temperature deformation. Therefore, problems with overheating are extremely rare with this motor.
Only in cases where car owners do not notice existing problems with the cooling system and operate the engine for a long time in conditions of constant overheating, warping of the cylinder head may be observed, which leads to the need to replace this unit. That is why we recommend regularly replacing antifreeze and inspecting the condition of all elements of the cooling system.
Maintenance
The 1.9 D engine from Audi, despite the use of numerous electronic systems, turned out to be quite reliable and easy to use.
Its repair and maintenance is not difficult. Moreover, most service work can be performed independently, saving on the use of the services of professional craftsmen.
You just need to remember that there is a timing belt drive, which forced you to undergo appropriate service work every 50 thousand kilometers, changing the rollers and belt. This work was carried out using special equipment that made it possible to set the gaps. It will be difficult to carry out such a timing belt replacement on your own without using the appropriate equipment.
If we talk about service activities, we note the need to change the oil every 10,000 kilometers. Otherwise, problems with the rings appeared, and the engine began to smoke mercilessly.
Malfunctions
| FAULT | CAUSE |
|---|---|
| The engine has lost most of its power and responds poorly to pressing the gas pedal. | There may be several reasons for this behavior of the motor. You must first check the condition of the fuel filter and fuel pump. Often, due to the use of low-quality fuel, the filter becomes clogged and the pump cannot push through it, providing the required pressure in the system. In some cases, it is necessary to open the engine and carry out a major overhaul. |
| There is strong vibration at idle. | This is due to damaged engine mounts, which over time lose their strength and the engine begins to shake on the mounts. Repair in this case consists of replacing damaged pillows. This work can be done on a special stand by raising the engine in the engine compartment. |
| The engine is full of oil, the corresponding indicator is on. | The weak point of this engine is the valve cover gasket, which usually withstands 20,000 kilometers at most. After which a noticeable leak appears, through which the engine quickly expels oil. The repair consists of replacing the valve cover head and correspondingly changing the engine oil. Only in rare cases is thermal overheating of the engine observed when cracks appear in the cylinder head. If such damage is present, the cylinder head must still be replaced, which leads to significant costs for the car owner. |
| Fuel consumption has increased significantly. | The reason may be improper operation of the injection system, or errors in the engine control unit, which prepares an excessively rich mixture. In any case, it will be necessary to carry out high-quality diagnostics, open the engine and inspect the condition of the engine. |
Tuning
Increasing the power of this power unit is not particularly difficult, so many car owners decide to perform tuning:
- The simplest and most effective way to increase engine power is to install a turbine from the next generation 1.9 TDI engine. It is only necessary to mount the turbine, replace the oil pump and engine control unit. Such work will allow us to obtain about 30 additional horsepower. Among the advantages of this tuning option, we can note the complete preservation of engine life, so such charged motors can run about 500 thousand kilometers without requiring major repairs.
- Deep engineering tuning involves the simultaneous installation of a turbine, as well as the replacement of pistons, crankshaft, flywheel and other power elements of the engine. As a result, such a motor is capable of developing about 150 horsepower. However, it should be taken into account that such tuning negatively affects the service life of Audi engines, which may require major repairs after 200 thousand kilometers.
- The so-called light tuning option is also possible, when the air filter is replaced, the engine control unit is replaced and the exhaust system is changed. In this case, the car owner, depending on the exhaust systems used, can receive from 15 to 25 horsepower. The replacement parts are not too expensive, and you can do all the work yourself.
The 1.9 TDI power unit is another representative of German-made diesel turbocharged power units from the Volkswagen concern. This engine is familiar to many car enthusiasts thanks to the VW Caddy, which has gained popularity.
Specifications
The 1.9 TDI engine (AFN, 1Z, AAZ, AHU) is a power unit that is installed on Audi, Skoda and Volkswagen cars. This is a diesel solution to many problems - especially traction and power.
1.9 TDi engine under the hood of a VW Passat.
Volkswagen 1.9 turbodiesels appeared in 1991 on the VW Passat B3. The engine uses a cast iron cylinder block with a forged crankshaft and a stroke of 95.5 mm. Pistons with a diameter of 79.5 mm, which makes it possible to obtain 1.9 liters of volume.
The first AAZ turbodiesels were equipped with an aluminum single-shaft 8-valve head with pre-chambers. The diameter of the intake valves was 36 mm, the exhaust valves were 31 mm, and the diameter of the valve stem was 8 mm. Then the 1Z, AHU, AFN and other engines appeared, which used a cylinder head with direct injection. The valve diameter here is 35.9/31.5 mm, the stem diameter is 7 mm.
The camshaft rotates via a timing belt, which needs to be changed every 60 thousand km. The first versions were equipped with a mechanical injection pump, then the engine was switched to direct injection.
Let's look at the main technical characteristics of the EA189 motor:
Name | Index |
Manufacturer | |
1.9 liter (1896 cc) |
|
Number of cylinders | |
Number of valves | |
Injection system | |
Power | |
Fuel consumption | |
Cylinder diameter | |
Oil used | 5W-30, 5W-40, 10W-40 |
How much oil is in the engine | |
400+ thousand km |
|
Applicability | VW Caddy |
Modifications
Like many engines produced by VW, the TDi 1.9 received a fairly large number of modification models with advanced characteristics:
- AZZ (1991 - 1998) - pre-chamber diesel with a compression ratio of 22.5 and a mechanical injection pump. There were two versions of the AAZ: with a Garrett TB0261 turbine and with a KKK K03. Both options were without an intercooler, the boost pressure was 0.7 bar. This internal combustion engine develops 75 hp. and 150 Nm of torque.
- 1Z (1991 - 1996) - direct injection turbodiesel with electronic injection pump, with different pistons and a compression ratio of 19.5. There is a Garrett GT1544S turbine with an intercooler, and the boost pressure is 0.95 bar. Power is increased to 90 hp, and torque is 202 Nm at 1900 rpm.
- AHU (1996 - 2001) - replacement for 1Z, which was adjusted to Euro 2 environmental standards.
- AFN (1996 - 1999) - analogue of AHU with a Garrett GT1744V-VNT15 variable geometry turbine, with different injector nozzles with larger holes and with a different ECU. Power 110 hp torque 235 Nm.
- ALE (1997 - 2000) - AHU engine for US environmental standards.
- AGR (1996 - 2005) - transverse version of the AHU diesel engine.
- ALH (1997 - 2010) - the same AGR for the North American market, but with a GT1749V turbine.
- AHH (1997 - 2001) - analogous to AFN, but differs in fuel injection pump, injectors and Garrett GT1749V turbine. Power 90 hp, torque 210 Nm.
- AHF (1997 - 2000) - analogue of ALH with sprayers, like on AFN.
- AVG (1999 - 2001) - renamed AFN.
- ASV (2000 - 2006) - replacement of AHF with different pistons.
- ABL (1992 - 2003) - analogous to AAZ, but with a different injection pump, with a Garrett TB0254 turbine, with a modified sump and a modified exhaust. Found only on Volkswagen T4.
Service
All VW-Group engines are serviced the same way. The TDI 1.9 diesel has a recommended service interval, according to the manufacturer’s standards, of 15,000 km. But, some motorists argue that to preserve the engine, it is necessary to reduce this figure to 10,000 km.
Malfunctions
Although the motor has proven itself to be reliable over its entire service life, it has a number of design flaws that are visible throughout the entire series:
Engine repair 1.9 TDI (AFN, 1Z, AAZ, AHU).
- White smoke from AAZ. Head depressurization. Repair or replacement of an element.
- Loss of traction. In almost all cases, the problem lies in the N75 boost control valve.
Conclusion
The TDI 1.9 engine is a good representative of turbocharged diesel engines, which are representatives of the old reliable generation. Maintenance and repairs are carried out quite simply and, as practice shows, usually on their own.
In the mid-90s of the last century, VAG management developed the TDI series - a turbodiesel with direct injection fuel injection pump. The first version of the AHU has a turbine with a bypass valve 75, which controls the opening of the bypass, regulating the volume of boost.
The AFN engine is a modernization of the TDI series:
- valve 75 changes the length of the turbine scroll, that is, the intake geometry;
- at low speeds this allows you to get rid of turbo lag;
- With a sharp increase in power, smooth control of the boost is maintained.
An important feature is the fact that in 1999 the VAG concern changed the designation of its engines; AFN was renamed AVG for the whole year. Each version of this series had a service life of 400,000 km.
Technical specifications AFN 1.9 l/110 l. With.
For the first time, a variable geometry turbine was used by VAG developers in the AFN engine. The only engine design that has perfect balancing is the in-line four, which is why it is used as the basis for the AFN internal combustion engine. To increase power immediately and much more, a turbine was installed, and to normalize parameters at low speeds, it was given variable geometry.
The AFN technical specifications look like this:
| Manufacturer | VAG |
| Engine brand | AFN |
| Years of production | 1996 – 2005 |
| Volume | 1896 cm3 (1.9 l) |
| Power | 81 kW (110 hp) |
| Torque moment | 235 Nm (at 4200 rpm) |
| Weight | 132 kg |
| Compression ratio | 19,5 |
| Nutrition | injection pump |
| Motor type | in-line diesel |
| Ignition | DIS |
| Number of cylinders | 4 |
| Location of the first cylinder | TVE |
| Number of valves on each cylinder | 2 |
| Cylinder head material | aluminum alloy |
| Intake manifold | duralumin |
| An exhaust manifold | cast iron |
| Camshaft | original cam profile |
| Cylinder block material | cast iron |
| Cylinder diameter | 79.5 mm |
| Pistons | cast duralumin |
| Crankshaft | 5 supports, 8 counterweights |
| Piston stroke | 95.5 mm |
| Fuel | diesel fuel |
| Environmental standards | Euro-3 |
| Fuel consumption | highway – 5.5 l/100 km combined cycle 6.8 l/100 km city – 8.5 l/100 km |
| Oil consumption | maximum 0.6 l/1000 km |
| What kind of oil to pour into the engine by viscosity | 5W30, 5W40, 0W30, 0W40 |
| Which engine oil is best by manufacturer | Liqui Moly, LukOil, Rosneft |
| Oil for AFN by composition | synthetics, semi-synthetics |
| Engine oil volume | 4.5 l |
| Operating temperature | 95° |
| ICE resource | stated 250,000 km real 500000 km |
| Adjustment of valves | hydraulic compensators |
| Cooling system | forced, antifreeze |
| Coolant volume | 7.5 l |
| water pump | Hi WP1097, Behr-Hella 8MP376800-341, Autlog WP7020 |
| Candles on AFN | Brisk S355, Bremi 26002, Bosch 0250202022 Duraterm, Beru GN855 |
| Spark plug gap | 1.1 mm |
| Timing belt | Bosch 1987949473, Stellox 09-04732-SX |
| Cylinder operating order | 1-3-4-2 |
| Air filter | Filtron AP073, Stellox 71-01113-SX |
| Oil filter | Bosch 0451103346, Alco SP-915, Febi 32378, Champion COF100150S |
| Flywheel | dual mass Quinton Hazell QDF138, Luk 415007510 |
| Flywheel mounting bolts | M12x1.25 mm, length 26 mm |
| Valve stem seals | manufacturer Goetze |
| Compression | 25 – 31 bar, boost 0.85 – 1.2 bar |
| Speed XX | 750 – 800 min-1 |
| Tightening force of threaded connections | spark plug – 17 – 25 Nm flywheel – 60 Nm + 90° clutch bolt – 13 – 25 Nm bearing cap – 65 Nm + 90° (main) and 30 Nm + 90° (rod) cylinder head – three stages 40 Nm, 60 Nm + 90° + 90° |
To make major repairs cheaper, the manufacturer provides a description of the characteristics and photos of the main operations in the motor’s instruction manual.
Design Features
The designers incorporated original design solutions into the AFN engine:
- in-line arrangement of 4 cylinders is the only scheme with ideal balancing, when the inertial forces are completely balanced;
- cast iron block and aluminum cylinder head to reduce the weight of the power unit;
- SOHC 8V timing mechanism;
- belt drive of timing drive and attachments;
- single coil ignition system with distributor;
- boost using a turbine;
- hydraulic compensators in the timing mechanism.
The performance of hydraulic pushers depends on the quality of the oil. Some attachments require periodic maintenance. For example, the pump is changed along with the timing belt, and the intake manifold is periodically cleaned from the inside to remove deposits.
The combustion chambers are tent-shaped, with the spark plugs inclined at the side of the center of the combustion chamber. The design of the engine does not have any complex solutions with the exception of hydraulic pushers. The cylinders are bored inside a cast iron block without liners, the surface is treated by honing. This makes it possible to increase maintainability and provide the possibility of further boring to increase engine power.
The EGR exhaust gas recirculation valve is most often turned off by the user. On the one hand, power increases, the design is simplified, and the amount of deposits inside the intake valve is reduced. On the other hand, the environmental standard is being reduced to Euro-0.
Advantages and disadvantages
The simple design of the internal combustion engine allows us to talk about this power drive as a motor with high maintainability and an almost complete absence of “sores”. This is a light, fast, economical turbodiesel with a long service life.
It is impossible to “kill” the induction electronics and the injection pump plunger of the “nine”. To eliminate periodic overcharging, it is enough to replace the EGR valve. Self-boosting the engine or complete overhaul does not cause problems and allows you to significantly save your operating budget.
Hydraulic compensators automatically adjust the thermal clearances of the valves. The only expensive spare part is the nozzle with needle sensor. The automatic belt tensioner often fails.
List of car models in which it was installed
The AFN in-line turbodiesel engine was used to equip the following Volkswagen models:
- Vento – in 1H2 body, classic sedan;
- Sharan – in 7M6, 7M8 and 7M9 bodies, minivan;
- Polo Classic – hatchback;
- Polo Estate – sedan;
- Polo Variant – 6KV5, station wagon;
- Caddy – 1995 – 2003, front-wheel drive van and minivan;
- Touran – compact van;
- Bora – hatchback;
- Passat sedan – in 3B2 body;
- Passat Variant – in 3B5, 3A5, 3A2 and 35I body styles, station wagon;
- Golf Mk III Cabrio – in 1E7 body, convertible;
- Golf III Variant – in 1H5 body, station wagon;
- Golf III Cabriolet – in the body 1E7, convertible;
- Golf III – in 1H1 body, sedan;
- Derby sedan – in the back of 6KV.
Similar engine specifications were required for Seat cars:
- Inca – 1995 – 2003, van;
- Cordoba – coupe and sedan;
- Cordoba Vario – station wagon;
- Ibiza is a hatchback.
In addition, these turbodiesels were equipped with the Skoda Octavia, Audi A3, A4 and A6.
Maintenance schedule AFN 1.9 l/110 l. With.
For users, the manufacturer has compiled a manual for the AFN turbocharged diesel engine, indicating the timing and maintenance operations:
- The manufacturer recommends replacing the timing belt together with the pump after 90 thousand mileage;
- Factory representatives advise updating the air filter annually or after 20 thousand km;
- According to the manufacturer, the engine oil and filter resource is 15,000 mileage;
- It is recommended to update antifreeze after 50,000 km;
- the exhaust manifold of engines begins to burn out after 70 - 90 thousand mileage;
- change the spark plugs yourself after 20,000 km, and change the battery within the time limits specified by its manufacturer;
- The fuel and air filters must be replaced after 30 and 20 thousand km, respectively.
The rest of the attachments have a long service life, so they are not serviced during maintenance. When replacing the belt, you should check the crankshaft gear for wear to avoid costly repairs. A gear is much easier to replace than a crankshaft.
Review of faults and methods for repairing them
The AFN turbocharged engine has the following malfunctions common to the entire TDI series:
In a turbodiesel, there is 100% collision of pistons/valves when the timing drive breaks. The rods here are directed strictly at right angles to the piston surface, so either the valve bends or the camshaft breaks, which is no better.
The service life of the timing belt here depends on the performance of the generator. If the overrunning clutch breaks, the tensioner breaks, the belt flies off or breaks with the above consequences.
Engine tuning options
Tuning will help boost the AFN engine to increase torque and improve dynamics:
- removal of partitions inside the air filter housing, enlargement of the suction window;
- installation of a direct fuel filter without return;
- dismantling the particulate filter;
- disabling the EGR exhaust gas recirculation valve, turning off the CO sensors and reconnecting the vacuum hoses;
- using an air filter cover without MAF, but with a soldered pipe of increased cross-section, for example, from an AAZ engine;
- using a 121 pin ECU via an adapter.
To complete the tuning, you will need to find a firmware version adapted to the changes made to the hardware. The nature of the internal combustion engine's operation at lower speeds will remain the same, but at high speeds there will be dynamics that are absent on the stock engine. Such tuning will add about 50 hp. With. without reducing service life.
Thus, the AFN engine does not have turbo lag due to the installation of a variable geometry turbine. Boost control via the 75 valve is very flexible, allowing for increased torque. This engine received a new designation AVG in 1999 and was produced under this marking for another year.
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