A crank sensor is a component used in an internal combustion engine to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control ignition system timing and other engine parameters. Before electronic crank sensors were available, the distributor would have to be manually adjusted to a timing mark on the engine.
The crank sensor can be used in combination with a similar camshaft position sensor to monitor the relationship between the pistons and valves in the engine, which is particularly important in engines with variable valve timing. It is also commonly the primary source for the measurement of engine speed in revolutions per minute.
Crank sensors in engines are usually comprised of magnets and an inductive coil. They are principally based on the Hall effect. Common mounting locations include the main crank pulley, the flywheel, or occasionally on the crankshaft itself.
Some engines, such as GM's Premium V family utilise crank position sensors which read a reluctor ring integral to the Harmonic Balancer. This is a much more accurate method of determining the position of the crankshaft, and allows the computer to determine within a few degrees the exact position of the crankshaft (and thereby all connected components) at any given time.
Crank Position Sensor Catalog
To find your Crank Position Sensor, once you select your year and make above, look for "Crank Position Sensor" on the right hand side.