why does my Genesis G70 have rough idle when cold

Solution

1. Preparation

• Gather tools such as an OBD-II scanner, socket set, multimeter, and cleaning supplies.
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Addressing Vacuum Leaks

• Inspect all vacuum hoses for cracks or disconnections.
• Replace any damaged hoses and ensure all connections are secure.

3. Spark Plug and Ignition Coil Replacement

• Remove the engine cover if applicable.
• Disconnect the ignition coils and remove them using a socket set.
• Remove old spark plugs using a spark plug socket and inspect their condition; replace if worn.
• Install new spark plugs with a torque specification of 13 ft-lbs.
• Reinstall the ignition coils, ensuring they are seated correctly.

4. Fuel System Inspection

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the 'ON' position (do not start) and check the pressure; it should match the manufacturer specification (typically around 40-60 psi).
• Replace the fuel filter if the pressure is low or if it hasn't been changed per the maintenance schedule.

5. Coolant Temperature Sensor Replacement

• Locate the coolant temperature sensor on the engine.
• Disconnect the electrical connector and remove the sensor using a socket set.
• Install a new coolant temperature sensor, ensuring it is tightened to manufacturer specifications.
• Reconnect the electrical connector.

6. Idle Air Control Valve Cleaning

• Locate the IAC valve on the throttle body.
• Remove it using a socket set and inspect for carbon buildup.
• Clean the valve using throttle body cleaner and a soft brush.
• Reinstall the IAC valve and reconnect it.