DIY Wastegate Tester

Wastegate testing is performed when the turbocharger has low charging system pressure. This prevents the car from getting a full boost from a turbocharger system. The wastegate is a part of a turbocharger that controls the direction of the exhaust gases, diverting them away from the turbine wheel. This protects the engine and turbocharger. The turbocharger allows car owners to get more power out of a smaller engine, without as much gas compression. Testing the turbocharger is a crucial part of troubleshooting it.

Instructions

1

Perform the Low Boost Pressure Test to determine if the low charging system pressure is resulting from a mechanical problem with the turbocharger. To do this, clamp the hose clamp around the actuating line of the wastegate. The actuator is a cylindrical object attached to a rod.

2

Perform a test drive on the vehicle to determine how much boost pressure is available.

3

Check the cars boost gauge to see if the boost pressure reaches 1.75 bar. If so, turn the car off and wait for the exhaust system to get cold.

4

Apply the parking break before jacking up the car. Put a wedge in front of the grounded front wheel. Place the hydraulic jack under the frame, where the jacking support point is located. Use the lever to place upward pressure on the bottom of the vehicle, slowly raising it up. Do not go under a car supported by the hydraulic jack alone. Instead, place a jack stand beneath the reinforced axle stand points.

5

Disconnect the wastegate actuating line from the wastegate. Connect a pressure pump to the wastegate. Lower the car before starting it.

6

Start the engine and let it idle. The exhaust line should be hot, but if the wastegate is closed and not leaking by, the bypass line should be cold.

7

Feel the bypass line while using the pressure pump to apply pressure to the wastegate. Start the air compressor.

8

Release the compressed air into the wastegate diaphragm. Do not apply more than 14.5 psi to the wastegate diaphragm. As the wastegate starts to open, the wastegate bypass line should get hotter. When removing the pressure, the wastegate should close and you will hear a click.

9

Turn off the engine and let the car cool. Adjust the opening part of the wastegate until it is opening and closing smoothly. Repeat the tests and test the exhaust line again to see if its hot. If it is, you successfully fixed the wastegate. If its cold, cool down the car and adjust the wastegate again.