Vacuum Leaks:
- Vacuum leaks create a lean fuel mixture, leading to rough idling and Check Engine Light illumination due to oxygen sensor readings.
Faulty Ignition Components:
- Issues with spark plugs, spark plug wires, or the ignition coil can disrupt proper combustion, resulting in rough idling and potentially triggering a Check Engine Light.
Fuel Injector Problems:
- Clogged or faulty fuel injectors can cause an inconsistent fuel supply to the cylinders, leading to rough idling and Check Engine Light activation.
Oxygen Sensor Issues:
- A malfunctioning oxygen sensor can provide incorrect feedback about the air-fuel mixture, which can cause rough idling and set off the Check Engine Light.
Throttle Position Sensor (TPS):
- A faulty TPS provides incorrect data about throttle position, disrupting the air-fuel mixture and leading to rough idling and a Check Engine Light.
Idle Air Control Valve (IACV):
- A faulty IACV can cause unstable idle speed, leading to rough idling and Check Engine Light illumination.
EGR (Exhaust Gas Recirculation) Valve Problems:
- Issues with the EGR valve, such as carbon build-up or sensor malfunctions, can cause rough idling and trigger the Check Engine Light.
Faulty Mass Air Flow (MAF) Sensor:
- An incorrect reading from the MAF sensor can affect the air-fuel mixture, resulting in rough idling and illumination of the Check Engine Light.
Transmission Issues:
- For vehicles with automatic transmission like Montero Sport, torque converter or valvebody issues can cause roughness at idle.
It's important to have a qualified mechanic diagnose the exact cause of the rough idle and illuminate the Check Engine Light in your Montero to ensure proper repair and prevent further issues. Using diagnostic tools and their expertise, they will pinpoint the root cause and advise on any necessary repairs or replacements.
