Shaanxi Automobile Delong's idle speed is unstable, high and low.

Too much carbon deposit on the throttle. There are many reasons for the unstable idle speed of Shaanxi Automobile Delong, such as excessive carbon deposition in the throttle, faulty valve timing, inaccurate valve timing, incorrect installation of timing belt, excessive carbon deposition in the intake and exhaust valves, and broken valve spring. , need 4s overhaul. Shaanxi Automobile Delong is a series of vehicles manufactured by Shaanxi Automobile Holding Group Co., Ltd., which mainly adopts wide-body extended Manfu 2000 cab, wide-body high-top extended Manfu 2000h cab, and 280, 320, 360 and 405 high-horsepower green engines to meet Euro II emission standards.