What Causes Car Shaking at Idle Speed?
2 Answers
The reasons for car shaking at idle speed: 1. Dirty throttle body and fuel injectors, requiring timely cleaning of the throttle body and engine carbon deposits; 2. Issues with the ignition system, mainly checking spark plugs, high-voltage wires, and ignition coils, with a focus on inspecting spark plugs. If excessive carbon buildup is found on spark plugs, replacement is recommended; 3. Unstable fuel pressure. It is advised to visit a 4S shop for professional diagnosis, as specialized computer analysis is required. Inspection items include fuel supply pressure, intake pressure sensors, etc., with replacement of damaged components if necessary. Car owners should take idle shaking issues seriously, as failure to address them promptly may lead to other problems.
My car also experienced idle shaking a few days ago. After inspection at the repair shop, three main issues were found: severe carbon buildup causing poor air intake and reduced combustion efficiency; aging ignition system with spark plugs that hadn't been replaced after 60,000 km and had excessive gap; completely collapsed right front engine mount with no damping effect left. The shaking is most noticeable at 600-900 rpm, making the steering wheel vibrate enough to numb hands. The mechanic said such issues should be addressed promptly as long-term neglect could increase fuel consumption and even damage the engine mounting system. He recommended first cleaning the throttle body and fuel injectors, checking carbon buildup in the cylinders, and performing dry ice cleaning if necessary. This would cost around a thousand yuan, much more cost-effective than replacing parts.
