Possible reasons for the drop in speed when turning on the automatic transmission:
*Faulty Throttle Position Sensor: This sensor tells the engine control unit (ECU) the throttle position, which affects RPM. A faulty sensor may send incorrect signals, leading to a drop in rpm.
* Damaged throttle cable: Some vehicles have a cable that controls the throttle position, which can become stuck or break, causing a drop in rpm.
* Clogged Throttle Body: Over time, the throttle body can become clogged with soot and deposits, restricting air flow and causing RPM to drop.
* Shift Mechanism Problems: Worn or damaged components in the shift mechanism may not engage the gears at the right time, resulting in a drop in rpm.
* Faulty Mass Air Flow (MAF) Sensor: This sensor measures the amount of air entering the engine and sends data to the ECU. A faulty MAF sensor can send incorrect signals, resulting in incorrect mixture adjustment and a drop in rpm.
* Problems with the electronic control unit (ECU): The ECU controls all engine systems and may be to blame for the drop in revs if it has problems.
Solution:
* Diagnose the problem using a diagnostic scanner.
* Clean or replace the throttle position sensor if it is faulty.
* Check the throttle cable and replace it if necessary.
* Clean the throttle body.
* Check the gear shift mechanism and repair it if necessary.
* Replace the mass air flow sensor if it is faulty.
* Have the ECU checked and repaired by a qualified mechanic.