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The Fuel Temperature Sensor (FTS) is installed into the secondary fuel filter. See Figure 25015 . The FTS sends an electrical signal to the ECM indicating fuel inlet temperature. The ECM uses this information to calculate fuel consumption. ‪

1.Secondary Fuel Filter ‪

3.Fuel Temperature Sensor ‪

2.Fuel Temperature Sensor Connector ‪

Engine Fuel Temperature Sensor

Replacement of FTS

The FTS is non-serviceable and should be replaced as a unit. No adjustment is required. ‪

Removal of FTS

Remove the FTS as follows: ‪

  1. Disengage the locking tang on the two-wire connector. Grasp the body of the connector and gently pull it from the socket.
  2. Use the appropriate wrench on the hex portion of the sensor and unscrew it from the fitting.

Installation of FTS

Install the FTS as follows: ‪

  1. The FTS is an electrical device. Use care in the installation process.
  2. Use Loctite Pipe sealer with Teflon J 26558-92 (or equivalent) on all but the first two threads of the FTS to prevent leaks.
  3. Install the FTS to the secondary fuel filter adaptor. See Figure 25015 .
  4. Install the two-wire connector and engage the locking tang.
  5. Turn the ignition to the "ON" position. Observe or read any diagnostic codes. If any code other than 25 appears, refer to Troubleshooting Manual, or call Detroit Diesel Technical Service (313) 592-7282.