my Skoda Octavia NFL (2020-Present) doesn't start when it's cold, what could be wrong

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to ensure safety during repairs.
• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, fuel pressure gauge.

2. Battery and Electrical System Check

• Use a multimeter to check the battery voltage; it should read at least 12.6 volts.
• If low, charge or replace the battery as necessary (ensure it’s fully charged before proceeding).

3. Starter Motor Inspection

• Remove the starter motor from the vehicle:
  • Disconnect wiring harness and battery terminal.
  • Unbolt the starter using a socket set and remove it.
• Inspect for any signs of wear or damage; test the starter on a bench tester if available.
• If faulty, replace with a new starter motor and torque bolts to manufacturer specifications (typically around 15-25 Nm).

4. Fuel System Check

• Inspect the fuel pump:
  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position (without cranking) and check for pressure (should be around 3-4 bar).
• If pressure is inadequate, replace the fuel pump.
• Change the fuel filter if it appears clogged; ensure to replace O-rings and tighten connections securely.

5. Coolant Temperature Sensor Replacement

• Locate the engine coolant temperature sensor and disconnect the wiring harness.
• Remove the sensor using a socket set; apply anti-seize lubricant on the threads of the new sensor.
• Install the new sensor and reconnect the wiring harness.