Why Does the Car Make Abnormal Noises When Starting?
1 Answers
Abnormal noises during car startup can be caused by the following reasons: 1. Hydraulic lifters: Air entering the hydraulic lifters due to low oil pressure or wear in the lifters themselves. 2. Valve clearance: Excessive valve clearance caused by wear in the valve rocker arms. 3. Dirty throttle body: Accumulation of sludge and carbon deposits leading to a dirty throttle body. 4. Carbon canister purge valve operation sound: This is a normal sound, and the car can continue to be used. However, if the noise is too loud, it is recommended to have it checked at a 4S shop. 5. Three-way catalytic converter: A "clicking" sound within half a minute after a cold start, which usually disappears afterward. This is typically the sound of the three-way catalytic converter expanding as it heats up.