Air Intake & Idle Control - Fuel, Air & Emission Symptoms
Common symptoms and diagnostic guides.
Sometimes idle seems to flutter up idle
Intermittent idle flutter (RPM surging up at idle) is often due to air intake, vacuum, or fuel delivery issues causing unstable idle speed and performance hiccups.
Engine revs up and down by itself
Erratic engine idle where RPM fluctuates up and down is usually caused by air?fuel mixture or sensor issues. Common causes include vacuum leaks, faulty idle control, and sensor faults that disrupt stable idle.