Possible Causes
Faulty Vacuum hoses damaged
Faulty Secondary Air Pump inoperative
Faulty One-Way Check Valve
الأسباب المحتملة
Possible Symptoms
Engine Light ON (or Service Engine Soon Warning Light)
Engine hesitation
الأعراض المحتملة
Description
The Air Injection (AIR) System refers to an emissions control system used by some vehicle manufacturers. It is often called secondary air injection, because air, more specifically oxygen, is injected into the exhaust manifold after start up. Vehicles start on a comparatively rich mixture to allow for smoother running conditions. However this has a large impact on exhaust gas emissions. A notable increase in hydrocarbon (HC) and carbon monoxide (CO) emissions is found under these rich start conditions. By injecting air in to the exhaust manifold the CO and HC can be oxidised. This reaction increases the temperature within the exhaust and the exhaust gas after treatment system i.e. catalytic converter can begin working earlier due to meeting its light off temperature.
The system consists of an air pump, one way check valve and associated pipework. The system operates for a predetermined time after start up. Normally this duration is approximately three minutes, when cold.