The cold car started with a whistle.

Reasons for the car's horn honking in cold start: 1, hydraulic tappet: due to low oil pressure or wear of the hydraulic tappet itself, the hydraulic tappet enters the air and produces abnormal sound; 2. Valve clearance: the valve rocker arm is seriously worn, resulting in excessive valve clearance; 3. Dirty throttle: a dirty throttle caused by the continuous accumulation of sludge and carbon deposits; 4. Working sound of carbon canister solenoid valve: This is a normal sound and can be used continuously. If the noise is too loud, it is recommended to go to the 4S shop for inspection.