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Home >> Chevrolet >> 1995 >> C3500 HD 6.5 F, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Controls - Adjustments - 6.5L Diesel >> Injection Pump Timing >> TDC Offset Learn Procedure
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TDC Offset Learn Procedure

NOTE: It takes PCM 20 seconds to learn TDC offset.

This procedure is only used when one of following conditions exists:

  1. Start and warm engine to normal operating temperature. Connect Tech 1 scan tester. Using scan tester, select OUTPUT TEST or INJECTION PUMP mode, and activate TDC OFFSET LEARN.
    NOTE: If engine stalls when "TDC TIME SET" is activated, turn engine off, then slightly rotate injection pump toward driver's side of vehicle. Tighten mounting nuts and repeat step 1).
  2. If learned TDC OFFSET reading is between .00 and -.50 degrees, procedure is complete. If reading is not as specified, slightly rotate injection pump and repeat step 1). A 1-mm pump movement equals about 2 degrees timing.
  3. To achieve a negative reading, rotate pump toward driver's side. To achieve a positive reading, rotate pump toward passenger's side.