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The Turbo Boost Sensor (TBS) is threaded into the intake manifold. See Figure 27369 . The Series 50G natural gas engines use a wide range sensor that allows pressure measurement under conditions of either manifold vacuum or boost. ‪

1. Intake Manifold ‪

5. Bolt ‪

2. Intake Manifold Inlet ‪

6. Air Temperature Sensor ‪

3. Intake Manifold Gasket ‪

7. Bolt ‪

4. Cylinder Head ‪

8. Turbo Boost Sensor ‪

Turbo Boost Pressure Sensor Series 50G

This device is a pressure sensor that sends an electrical signal to the ECM. The ECM uses this information to compute the amount of air entering the engine. Fuel supply is regulated by the TBS information to control engine air fuel ratio. The TBS information is also used to control ignition timing. ‪

Repair or Replacement of Turbo Boost Sensor

The TBS is non-serviceable and must be replaced as an assembly. No adjustment is required. ‪

Removal of Turbo Boost Sensor

Remove the TBS as follows: ‪

  1. Disengage the locking tang on the TBS connector body. Grasp the terminal body and gently pull it from the sensor.
  2. Remove the TBS from the intake manifold.

Installation of Turbo Boost Sensor

Install the TBS as follows: ‪

Note: The TBS is an electronic device. Use care during installation.

  1. Install the TBS to the intake manifold.
  2. Engage the locking tang on the TBS connector body. Grasp the terminal body and gently pull it towards the sensor.
  3. Put petroleum jelly on O-ring to hold it in position.
  4. Turn the ignition to the "ON" position. Observe or read any diagnostic codes. If any codes other 25 appears, refer to the DDEC II Troubleshooting Guide , 6SE489, or DDEC III/IV Single ECM Troubleshooting Guide, 6SE497.