General information about the 4-cylinder engine (Audi A4 B6)

1.6 l (ALZ): The engine is in-line, with one overhead camshaft (OHC). The camshaft is located in the cylinder head and is driven by a toothed belt. The shaft acts on vertically positioned hydraulic tappets, which in turn act on the intake and exhaust valves.

1.8 and 2.0 l (AVJ, BFB, ALT): The engine is in-line, with two overhead camshafts (DOHC), has three intake and two exhaust valves for each cylinder. One camshaft drives the intake valves, the other the exhaust valves. The exhaust camshaft is driven by the crankshaft via a toothed belt. The intake and exhaust camshafts are connected to each other by a chain.

2.0L FSI (AWA): The engine is in-line, with two overhead camshafts (DOHC), has two inlet and outlet valves for each cylinder.

2.0L FSI 4-cylinder petrol engine

1 - Ignition coil
2 — camshaft of exhaust valves. The camshaft tilt motor is located at the rear end
3 — Intake camshaft. The front end houses the Hall sensor rotor, and the rear end houses the high-pressure fuel injection pump. Drive is provided by the exhaust camshaft via a chain
4 - Lever
5 — Injector
6 - Toothed belt
7 - Oil pump
8 — Electric motor for tilting the camshaft
9 — Throttle control unit
10 — Inlet manifold
11 — Vacuum accumulator
12 — Intake manifold switching shaft
13 — Intake manifold flap control motor
14 — Crankshaft

One camshaft drives the intake valves, the other the exhaust valves. The camshaft of the exhaust valves (1) is driven from the crankshaft (2) by a toothed belt (3). The camshafts of the intake and exhaust valves are connected by a chain (4). A rotary motor (5) is located at the rear of the camshaft of the exhaust valves, which can automatically shift the installation angle up to 42° the camshaft of the exhaust valves. In the rear part of the camshaft of the intake valves (6) there is a high-pressure pump of the direct injection system of gasoline. It is driven by a double cam (7) of the camshaft of the intake valves.