Procedure
1. Remove the vacuum hose.
Attention! The one-way valve is pressed into the vacuum hose in a certain position.
2. Use a vacuum pump to check the operation of the one-way valve.
The material was obtained from a web resource hyundaibook
| Connecting the vacuum pump | Criteria |
| From the brake booster side (A) | A vacuum is created and maintained |
| From the intake manifold side (B) | No vacuum is created |
Warning: If the one-way valve is faulty, replace it together with the vacuum hose.