Does the Audi A6 2.4 knock sensor distinguish between left and right?
1 Answers
Audi A6 2.4 knock sensors do distinguish between left and right. Detecting engine knock to suppress the occurrence of knock phenomena: When adjusting the knock sensor, engineers write the vibration pattern of knock into the electronic control unit. If the knock sensor detects the vibration pattern, the electronic control unit determines that the engine is knocking and then delays the ignition timing. Currently, advanced knock sensors can even determine which cylinder is knocking and delay the ignition timing of that cylinder separately. Knock sensors are installed in the middle of the engine cylinder block: For example, in a four-cylinder engine, they are installed between cylinders 2 and 3, or one between cylinders 1 and 2 and another between cylinders 3 and 4. They are used to measure engine vibration and adjust the ignition timing when the engine knocks. They are usually made of piezoelectric ceramics. When the engine vibrates, the ceramic inside is squeezed to generate an electrical signal. Because this electrical signal is very weak, the connecting wires of ordinary knock sensors are wrapped with shielded cables. Knock sensors are AC signal generators, but they differ significantly from most other AC signal generators in cars. In addition to detecting the speed and position of rotating shafts like magnetic crankshaft and camshaft position sensors, they also detect vibration or mechanical pressure. Unlike stators and magnetoresistors, they are usually piezoelectric devices. They are made of special materials that can sense mechanical pressure or vibration (for example, when the engine starts to knock, they can generate an AC voltage).
