What is the reason for the noise when releasing the throttle in neutral on the Baojun 730?
3 Answers
Baojun 730 makes a noise when releasing the throttle in neutral because the speed and gear are not properly matched. The matching between gears and speeds is as follows: First gear is for starting, with a speed generally between 0-5km/h; second gear corresponds to speeds of 5-20km/h; third gear corresponds to speeds of 20-40km/h; fourth gear corresponds to speeds of 40-60km/h; fifth gear corresponds to speeds of 60-100km/h. Sixth gear is for speeds between 100-120km/h. Timing for upshifting: When the engine has ample power, it emits a dull "humming" sound. If after upshifting there is no sign of insufficient power or shaking of the transmission mechanism, and the speed increases quickly with smooth and natural vehicle movement, it indicates the upshifting timing is accurate.
It's quite common for my car to make a noise when I let off the gas after driving for a long time. For models like the Baojun 730, abnormal sounds when releasing the throttle at idle are mostly due to issues with the exhaust pipe or chassis components. A loose exhaust pipe joint or missing fastening bolts can cause the exhaust system to vibrate and hit the body, creating noise. Engine mounts may also age and deform, causing the engine to shake and hit the chassis when the throttle is released. Another possibility is a loose differential mount in the drivetrain, especially after years of driving when rubber parts tend to fail. Last time I went for maintenance, the technician mentioned that regular checks on these areas can prevent noise. If the sound is a metallic 'clunk,' it should be addressed immediately, as it could lead to accidents at high speeds. Keeping the engine clean and reducing carbon buildup can also help it run more smoothly. In short, don't wait until the problem worsens; a small investment can fix it early on.
That sudden noise when lifting off the throttle is indeed concerning. Having driven the Baojun 730 for several years, I've found this issue often stems from the drivetrain. Worn differential bearings or excessive driveshaft clearance can cause impact noises during deceleration, especially noticeable during idle when load changes rapidly. A detached exhaust heat shield or leaking exhaust manifold might also produce a sudden 'puff' of escaping air. I recommend first inspecting chassis suspension components, such as loose torsion bar mounts – Baojun's chassis design in older models was prone to resonance. If the sound is a persistent 'squeak', also check for insufficient belt tension causing pulley slippage. A quick DIY check is shaking the exhaust pipe to detect looseness, then visiting a shop for OBD diagnostics. Repair costs are generally low, preventing potential engine or transmission damage. In daily driving, proper gear shifting and avoiding sudden acceleration can reduce component stress and extend lifespan. Addressing these minor issues promptly ensures both driving comfort and safety.
