What's the reason for the car not accelerating while driving?
3 Answers
The reasons why a car cannot accelerate while driving: 1. Low fuel pressure or air in the fuel line, poor signal from the air flow meter in the circuit, poor signal from the throttle position sensor, damaged ignition coil, delayed ignition timing, or incorrect spark plug gap (either too large or too small) can all cause the car to fail to accelerate when stepping on the gas pedal. In addition, a clogged three-way catalytic converter could also lead to this condition. Moreover, if the engine speed rises normally but the engine noise is loud, it might be in a neutral idling state without being in gear, requiring inspection of the transmission. 2. Poor quality fuel used by the owner can affect the gasoline filter and fuel line, possibly leading to poor fuel supply and thus failure to accelerate. It can also impact the lifespan of the exhaust system's three-way catalytic converter. If the three-way catalytic converter is clogged, it will directly affect the vehicle's acceleration performance and also lead to increased fuel consumption.
I usually encounter this situation due to a fuel pump issue. Once on the highway, pressing the accelerator felt like stepping on cotton, and the car body was jerking. After stopping to check, I found the fuel pump filter screen was clogged, cutting off gasoline supply. It could also be caused by a fuel filter that hasn't been replaced for too long, or impurities entering the fuel tank. If the car stalls easily when hot, the fuel pump is more likely to be aging. The scariest scenario is fuel line leakage – not only can't you accelerate, but you can also smell gasoline, requiring immediate pulling over. Also, check if the fuel gauge is almost empty, as some cars experience unstable fuel supply when the level is too low. Don't force driving when facing such problems; the safest approach is to find a secure spot to stop and inspect.
When driving older models, I often encountered sluggish acceleration issues, which were primarily caused by ignition system problems. After prolonged use, spark plug electrode erosion leads to weak ignition, especially noticeable when climbing hills. A mechanic taught me to use an OBD scanner to read trouble codes, and it turned out to be a cracked ignition coil leaking electricity. Another time, the crankshaft position sensor was clogged with oil sludge, causing signal failure and fuel delivery confusion. Nowadays, when facing such situations, I first check if the engine warning light is illuminated on the dashboard. Additionally, a dirty mass airflow sensor can cause the ECU to miscalculate fuel injection—cleaning it usually solves the problem. I remember one instance where poor fuel quality caused partial clogging of fuel injectors, with symptoms also including delayed throttle response.
