شل بودن یا نبود درب هواکش

The airbox lid loose or absent, so air enters unfiltered and unmeasured. It is both faults at once — dust reaches the airflow sensor's element and the bore, and air bypasses the measurement.

The complaint is often a noise before it is a warning light: an intake roar or whistle under acceleration that the owner mentions first. Fuel trims run positive and the idle hunts. Check every clip is engaged and the lid sits flush — a lid clipped at one end and proud at the other is the classic, and it is nearly always a service that was rushed. A missing lid is also a fire and water risk in an engine bay, so it is worth more than a note on an invoice.