why is my Toyota Corolla E170 (2013-2019) making a hissing noise

Solution

1. Preparation

• Tools Required: OBD-II scanner, mechanic's stethoscope, basic hand tools (sockets, wrenches), flashlight
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Locate and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. If visible damage is found, replace the damaged hoses with new ones.
  3. If no visible damage is found, use a smoke machine or carburetor cleaner to identify leaks by observing changes in engine RPMs.
  4. Tighten any loose clamps and connections.

3. Inspect and Repair the A/C System (if applicable)

• Sub-steps:
  1. Check A/C lines and connections for signs of leaks or wear.
  2. If a leak is found, repair or replace the damaged line.
  3. Recharge the A/C system as per the manufacturer’s specifications.

4. Inspect Exhaust System

• Sub-steps:
  1. Visually inspect the exhaust manifold and pipes for cracks or holes.
  2. Use a wrench to tighten any loose connections.
  3. If damage is found, remove the affected section and replace it.