What Causes Engine Stalling at Idle?

[LaLila]

The causes of engine stalling at idle need to be analyzed based on the symptoms. If the engine stalls immediately upon entering idle operation, this is referred to as "no idle speed." Common causes for this issue include: damage to the engine idle control valve or its wiring; leakage in the vacuum pipe of the brake vacuum booster; rupture of the brake vacuum booster diaphragm; intake manifold air leakage; or problems with the idle control module in the engine electronic control unit (ECU). For intermittent idle stalling, typical causes include: sticking of the engine idle control valve; worn insulation on the idle control valve wiring; excessively dirty idle air passages; issues with the engine throttle position sensor; problems with the camshaft position sensor or crankshaft position sensor; malfunction or excessive dirt on the engine speed sensor; or faults in the idle control program within the engine electronic control unit.