Some of the common sensors involved are;
Camshaft Position Sensor replacement
The camshaft position sensor monitors the rotation of the camshaft, specifically targeting when valves open and close. Most camshaft sensors are mounted just above a notched ring on the camshaft. Most of these camshaft sensors will use a magnet to produce or vary an AC electronic signal that is used in conjunction with a crankshaft position sensor to determine when a position approaches top dead center (TDC) on the compression stroke. This information will help to fine tune spark timing and injector pulse.
Crankshaft Position Sensor Replacement
The crankshaft position sensor monitors the rotation of the crankshaft, specifically targeting when the number one piston reaches top dead center (TDC) in the cylinder. Most crankshaft sensors are mounted just above a notched ring on the crankshaft or above the flywheel. These sensors use a magnet to produce or vary an AC electronic signal that is used in conjunction with a camshaft position sensor to determine when a position approaches top dead center (TDC) on the compression stroke. In modern engines, with advances in variable valve timing and direct injection, the crankshaft position sensor is the most important input for the on board computer.
Mass Air Flow Sensor Replacement
For most of the modern engines on the road, the mass air flow sensor is the most important electronic input for the onboard computer to make decisions on air-fuel ration. The sensor sits in the air induction system usually right after the air filter. Using a heated wire or possibly a vane meter the sensor measures the rate and density of the air moving into the engine. This helps the on-board computer to shorten or lengthen the fuel injector open time to meet the ideal ratio of 14.7 parts air to 1 part fuel.
Throttle Position Sensor Replacement
The throttle position sensor measures the opening and closing of the butterfly valve inside the throttle body. It is viewed as a feedback sensor to the on board computer in relation to driver command on the accelerator, idle control, and accessory demand (AC, power steering) on power. Many modern cars run on “fly by wire” technology, where the cable from the accelerator to the throttle has been eliminated and the computer now controls the opening and closing of the throttle in response to the accelerator position sensor.
Symptoms:
A fault on any of these sensors will be notified by ECU error codes, and a stalled engine. This needs to be diagnosed manufacturer approved software for effective diagnosis. It is best to switch of your car and hire a recovery van.