What to Do When the Tachometer Needle Fluctuates During Cold Start?

[LaHeidi]

Solutions for fluctuating tachometer needle during cold start are as follows: 1. Check the throttle valve: Inspect if the throttle valve is excessively dirty, clean and recalibrate it. 2. Inspect the intake system: Check for excessive carbon buildup in the engine intake system and fuel injectors. Perform a no-disassembly cleaning and replace the fuel filter. Note: For gasoline engines, when the ambient temperature is not lower than -5°C, and for diesel engines, when the ambient temperature is not lower than 5°C, up to three start attempts (including three) are allowed, with each attempt not exceeding 5 seconds, and the engine must start successfully. Under normal operating temperature, the engine should start successfully within 5 seconds in one attempt. After a cold start, the engine warm-up process should comply with the original design specifications regarding RPM.