The first gasoline engines with direct injection on Audi, Skoda, Volkswagen cars appeared in the early 2000s. But before launching a line of such power units, VAG engineers adapted the old 1.6-liter 16-valve motor (BAD, family EA113) to this type of injection. That is, this motor turned from MPI to FSI. And in the beginning of 2002, new engines with direct injection appeared on VAG cars. The firstborn was a turbo motor 1.4 TSI (AXU) with an output of 86 hp, which was installed on Polo. It was followed by atmospheric engines with direct injection, based on the same block. At the beginning of 2003, an atmospheric 1.6 FSI (BAG) engine with an output of 115 hp was introduced. Then a rare 1.4 FSI (BKG, BLN) atmospheric engine was presented.
It can be said that the 1.4 FSI and 1.6 FSI direct-injection engines are derived from distributed injection (MPI) motors of the same displacement. They have the same cylinder bore of 76.5 mm and piston stroke of 75.6 and 86.9 mm for the 1.4- and 1.6-liter, respectively.
But the FSI engine family has switched to an aluminum block, and the timing drive has a chain instead of a set of two toothed belts. And, most importantly, the compression ratio was raised to 12:1, so FSI-engines have to be fed only 98-m gasoline. The power will be lower on 95.
With the transition to direct injection FSI-engines became a little like diesel engines. In particular, they had to install a high-pressure fuel pump, which is a bit simpler than the diesel pump. There was a fuel ramp (distributor) with a high-pressure sensor. And on the supply line – a low-pressure sensor. And in general, the engines 1.4 TSI and 1.6 FSI are the same unit, differing in working volume and the presence of a turbine in the younger.
Technical characteristics
| Characteristics | Value |
|---|---|
| Exact volume | 1598 cm³ |
| Power system | direct injection |
| Engine power | 115 hp |
| Torque | 155 Nm |
| Cylinder block | aluminum R4 |
| Cylinder head | aluminum 16v |
| Cylinder diameter | 76.5 mm |
| Piston stroke | 86.9 mm |
| Compression ratio | 12 |
| Engine Features | DOHC |
| Hydrocompensators | yes |
| Transmission timing | chain |
| Fasoregulator | in intake |
| Turbocharger | no |
| What oil to use | 3.6 liters 5W-30 |
| Environmental class | Euro 4 |
| Example service life | 240,000 km |
Design features and problems of the 1.6 FSI engine
Decorative cover
The decorative cover of the 1.6 FSI engine is not so decorative. It houses the air filter, the thermostat for warm air intake, and the intake air temperature sensor.
Inlet manifold
The intake manifold contains flaps that cover the intake passages when the engine is under low load. The flaps can become jammed or the valve that controls them can fail. This usually causes the engine to jerk during smooth acceleration.
There is another air temperature sensor and an air pressure sensor in the intake manifold. The atmospheric pressure sensor is in the engine control unit. All this is necessary for the engine to calculate the amount of intake air. There is no mass air flow meter on this engine. Well, as you have already begun to guess, if these sensors begin to glitch, then without a good diagnostician the problem with the unclear behavior of this engine can not be solved.
Fuel pump
The fuel pump on the 1.4 FSI, 1.4 TSI, 1.6 FSI engines of the first generation (BKG, BLN, AXU, BAG, BLP, BLF) are the same.
By design, the fuel injector is a variable-flow single-plunger high-pressure pump. The pump delivers fuel to the distributor at a pressure of 100 bar and only in the quantity to be injected. Unlike a diesel engine, there is no constant reverse flow of fuel. Gasoline can only escape into the return through a safety valve, which is triggered at a pressure of 120 bar.
The pump is driven by a cam on the camshaft. Between them there is a small tappet. If it is not replaced in time, the tappet will rub through and the plug stem will contact the camshaft cam. If the tappet is wiped, the performance of the fuel injector is drastically reduced. In addition, chips from its surface get into the oil. The tappet is easy to change and is cheap. It should be changed once in 3-4 years.
The fuel injector itself is not eternal, it wears out due to the use of low-quality fuel. Problems with it are manifested in a decrease in engine power and errors in terms of pressure in the ramp.
Thermostat
The cooling system has two circuits of coolant circulation. The fluid flows through the cylinder head and through the cylinder block are separate and can have different temperatures. The antifreeze that is pumped through the block can heat up to 105 degrees. The temperature in the cylinder head is slightly lower. The flows are controlled by two thermostats located in a common housing. One of the thermostats controls fluid flow through the cylinder block, and the other controls fluid flow through the cylinder head. A good new thermostat costs about 60 ue.
EGR valve
FSI engines are diligent about fighting nitrogen oxides in the exhaust. As with diesels, the only way to win this “battle” is to lower the combustion temperature by reducing the amount of oxygen. To do this, inert combustion gases must be sent to the cylinders. This is the responsibility of the exhaust gas recirculation system – EGR. Exhaust gases and gases from the crankcase ventilation system also contaminate the throttle valve and settle on the intake valves. The choke can be cleaned, but the valves are more difficult.
Nitrogen Oxide Sensor
The most expensive sensor on an FSI engine is located after the catalytic converter and measures the amount of nitrogen oxides. Sensors manufactured until about the end of 2004 were defective and were replaced. But a fixed nitrogen oxide sensor can fail due to poor quality gasoline. Earlier such a sensor, going together with a small control unit, cost 800 ue. Now it is more than 2 times cheaper. However, this sensor can be simply blown off.
Valve cover
The valve cover gasket does not last long. It starts leaking oil after 100,000 – 150,000 km of mileage.
Phase shifter
The phase shifter with hydraulic clutch is mounted on the intake camshaft and is controlled by a valve. Failure of the phase shifter is manifested by a buzzing noise when starting the engine, which disappears after about 10 seconds. It is not uncommon for the phase shifter valve to fail either.
The timing chain
The 1.6 FSI engine uses a chain in its timing drive. It is not a roller chain, but a slotted or toothed chain, a Morse chain. This chain is quieter than a roller chain, but is extremely sensitive to the quality of lubrication. In general, there are no complaints about it. There are questions about the quality of its manufacture. On FSI motors, it was stretched, which is expressed in the appearance of noise or errors in synchronization of the crankshaft and camshafts. By the way, a set of this chain is not much more expensive than a set of timing belt of FSI predecessors: the chain with tensioner and a pair of calipers is literally 10-20% more expensive than a set of belts and rollers (if we take the prices of good manufacturers).
Also, the first FSI engines introduced their owners to the fact that it is impossible to leave the car in gear on a slope. Only the handbrake! FSI engines taught unknowing FSI owners a very expensive lesson: the chain would jump and the pistons would bend the valves on startup. The thing is, the hydraulic chain tensioner rod has no stopper. Therefore, at the stopped engine at the absence of oil pressure and arising at parking on a slope chain tensioner is pressed in. And when the engine is started, the hydraulic tensioner simply does not have time to do its job. That’s why the chain slips.
The timing chain kit was used until 2014 on the 1.4 TSI and even on the 105 hp 1.6 CFNA.
Oil pump
A variable oil pump debuted on FSI engines, capable of maintaining oil pressure at 3.5 bar over virtually the entire operating speed range. The pump is fully mechanical and highly reliable.