What are the reasons for no response when stepping on the accelerator in a JMC Shunda?
4 Answers
The reasons for no response when stepping on the accelerator in a JMC Shunda are as follows: Dirty throttle body or excessive carbon buildup in the fuel injectors: After driving a certain distance, a dirty throttle body can cause it not to close tightly or the idle speed stepper motor to get stuck, both of which can result in excessively high engine idle speed. Additionally, carbon deposits generated during engine operation can cause vehicle vibration, especially when starting the vehicle. The engine may vibrate more severely than usual or even fail to start on the first attempt. Therefore, when the vehicle experiences vibration, the throttle body and fuel injectors should be inspected first. If the throttle body is found to be dirty or the fuel injectors have excessive carbon buildup, they should be cleaned promptly. Aged engine mounts: Vehicle vibration can sometimes be related to aging engine mounts. Engine mounts are essentially the shock absorption system for the engine, responsible for absorbing minor vibrations during engine operation. If the engine mounts are faulty, these vibrations can be transmitted to the steering wheel and the interior of the vehicle, causing vibration at idle. When the car engine is idling, activating the electrical system is most likely to cause vehicle vibration, as the engine load increases due to the operation of the electrical system.
I drove a JMC Shunda for long-distance trips for several years and encountered the issue of the accelerator pedal not responding when pressed, which was quite annoying. There are several common causes: it could be a faulty accelerator pedal position sensor, a dirty sensor or poor contact preventing the signal from reaching the computer; or excessive carbon buildup in the throttle body blocking airflow, leaving the engine powerless; or a problem with the fuel system, such as a clogged fuel filter or a failing fuel pump cutting off fuel supply, directly causing loss of power. I remember that time on the highway when I pressed the accelerator and the car didn’t move at all, scaring me into pulling over immediately. I first checked the fuse box myself to see if any fuses were blown, but most of the time, I had to go to a repair shop to diagnose it with a scanner. Prevention is simple—regularly cleaning the throttle body and checking the fuel system can save a lot of trouble. Safety first—don’t force it to avoid accidents.
I've been driving my Shunda to work for over a year. Once, right after starting the car, pressing the accelerator had no response at all—it was completely dead. After checking, it turned out to be either an electronic throttle failure or a faulty air flow meter, where the sensors weren't working properly and the signals were chaotic; it could also have been due to an aging fuel pump not supplying enough fuel, especially during long drives when the fuel line gets clogged, making it more prone to happen. I went to the repair shop myself and replaced the faulty parts, which solved the problem, but it took some time. It's important to develop good maintenance habits, like checking the fuel filter and cleaning the sensors every quarter to prevent carbon buildup. If you encounter accelerator failure on the road, don't panic—turn on your hazard lights, slow down gradually, and pull over to a safe spot to handle the situation. These kinds of issues are common in older cars or those with insufficient maintenance, and fixing them early can extend the car's lifespan.
Over ten years of repairing cars, I've encountered many cases of unresponsive throttles in the Shunda model. Typically, the issue stems from loose or broken throttle wiring, preventing signal transmission; a faulty electronic throttle position sensor can also cause the engine to fail receiving commands; another possibility is that the ECU control unit requires resetting or recalibration. The troubleshooting process is straightforward: first, use a multimeter to check for short circuits in the wiring and inspect the fuse box for any burnt fuses; if that doesn't resolve it, connect a diagnostic computer to retrieve data. Safety is paramount—if the throttle becomes unresponsive while driving, pull over immediately and avoid pushing through to prevent accidents. Regular maintenance can help avoid such issues. It's recommended that owners clean throttle carbon deposits every six months and not neglect fuel system maintenance.
