Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1997CHEVY EXPRESS G3500, VAN CARGO, 6.5 FREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 115 (ENGINE PERFORMANCE SYSTEM ADJUSTMENTS - 6.5L TURBO DIESEL)INJECTION PUMP TIMINGTDC OFFSET LEARN PROCEDURE
1997 Chevrolet Chevy Express G3500, Van Cargo, 6.5 F
TDC Offset Learn Procedure
1997 Chevrolet Chevy Express G3500, Van Cargo, 6.5 FSECTION TDC Offset Learn Procedure
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 1998 GMC Savana Special, 1998 GMC Savana Camper Special, 1998 GMC Savana, 1998 Chevrolet RV Cutaway, and 1998 Chevrolet Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
This procedure is only used when one of following conditions exist:
- DTC P1214 is set.
- Engine has been replaced.
- Front engine cover has been replaced.
- PCM and injection pump have been replaced.
- Start engine and allow it to reach normal operating temperature. Connect Tech 1 scan tool. Clear all DTCs. Turn ignition on, with engine off. Using scan tool, select OUTPUT TEST/INJ PUMP mode. Activate TDC OFFSET LEARN.
- If learned TDC OFFSET reading is between -.25 and -.75 degree, procedure is complete. If reading is not as specified, hold accelerator pedal in wide open throttle position for at least 45 seconds. Turn ignition off for 30 seconds. Start engine. TDC OFFSET reading should be zero. If reading is not zero, repeat step 1).
- With engine running, PCM will learn new TDC OFFSET when normal operating temperature is obtained and engine speed is less than 1500 RPM. New TDC OFFSET will overwrite previous reading. If new learned TDC OFFSET reading is not between -.25 and -.75 degree, turn ignition off.
- Slightly rotate injection pump and repeat step 1). A .039" (1.0 mm) pump movement equals about a 2 degree timing change. To achieve a positive reading, rotate pump toward driver's side. To achieve a negative reading, rotate pump toward passenger's side.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.