What Causes High Engine RPM but No Increase in Speed When Pressing the Accelerator?
2 Answers
Introduction to the reasons why the car's speed does not increase while the engine RPM is high when pressing the accelerator: Using a manual transmission: The most common reasons are issues with the clutch and the transmission. The clutch acts as an intermediary for power transfer between the engine and the transmission. If the clutch friction plate is slipping, it can lead to a loss of power. Manual transmissions have high transfer efficiency. If the clutch is functioning properly, the possible faults could be related to the output shaft or the meshing gears of the selected gear. Using an automatic transmission: The most common reason is the torque converter not locking up. Normally, when the engine RPM, vehicle speed, and throttle depth reach certain levels, the torque converter locks up. Before this happens, it is common to experience a situation where pressing the accelerator results in high RPM but no increase in speed. This phenomenon mainly occurs in vehicles equipped with torque converters, such as all ATs and some CVTs. In this regard, dual-clutch transmissions perform much better.
I've been driving for over a decade and have encountered several situations where the engine roars loudly when I press the accelerator but the car doesn't speed up. The most common cause in manual transmission vehicles is clutch slippage - if the clutch disc is severely worn or improperly adjusted, power won't be transmitted to the wheels. For automatic transmissions, it could be a gearbox issue like a faulty torque converter causing poor transmission efficiency. Another possibility is insufficient fuel supply or unstable ignition system resulting in inadequate engine output despite high RPMs. My suggestion is to start with simple self-checks: when parked, shift to neutral and press the accelerator to see if the RPM surges normally. If it does, the engine is probably fine, then check transmission fluid level or clutch pedal clearance. Never delay repairs as this could damage more components and increase repair costs. Getting professional diagnosis promptly is crucial - safety always comes first.
