The electronic gas pedal is mounted on the engine compartment bulkhead.
Electronic gas pedal: 1 — gas pedal mounting bracket with sensor; 2 - gas pedal
Based on signals received from the gas pedal position sensor, the electronic control unit (ECU) determines the required amount of air and fuel supplied to the engine cylinders. In this case, the ECU takes into account not only the amount by which the gas pedal has shifted, but also the engine operating mode, and sends the appropriate commands to the throttle assembly and fuel injectors.
In essence, the driver, by pressing the gas pedal, only indicates what acceleration he would like to give the car, and the engine management system implements this. The same thing happens when the driver releases pressure on the gas pedal, holds it pressed in one position, or takes his foot off it completely. As a result, the optimal composition of the combustible mixture is constantly maintained in the cylinders under any engine operating mode.
The sensor is a potentiometer with two conductive tracks. As a result of wear of the moving contact or conductive tracks, the sensor may fail or the signals coming from it will be incorrect. In this case, the engine will operate unstably, and "failures" are possible during transient conditions. When idling, the engine crankshaft speed may increase spontaneously.
If the sensor or its circuit is faulty, the engine management system malfunction indicator lamp will light on the instrument panel.
The gas pedal position sensor cannot be repaired; in case of a malfunction, the electronic pedal is replaced as an assembly.
The need for replacement is determined during diagnostics of the engine management system.
Replacing the gas pedal
1. We prepare the car for maintenance and repair.
2. Disconnect the wire terminal from the battery terminal.
3. Press the lock and disconnect the wiring harness connector.
4. Inspect the contacts of the wiring harness connector. If oxides are found, treat them with a product for cleaning and protecting electrical contacts.
5. Using a 10 mm socket wrench, unscrew the mounting bolt and remove the gas pedal.
6. Install the gas pedal in the reverse order. Tighten the pedal mounting bolt to a torque of 10 Nm.
(The source of the article is available on the website: CHEVYMAN)