You cannot determine the correct fuel pressure without knowing the specific engine. To find the correct specification, you need to:
1. Identify your engine: Look for an engine identification plate usually located on the engine itself or in the engine compartment. This will tell you the exact engine model (e.g., 5.9L Cummins).
2. Consult your owner's manual: The owner's manual will specify the correct fuel pressure for your specific engine.
3. Check a reliable online repair manual: Websites like Chilton or Haynes offer repair manuals specific to your vehicle's year, make, and model. These manuals will contain the fuel pressure specifications.
Providing the engine details will allow for a more accurate answer.