1. Check the Engine ID Tag:
* Location: The engine ID tag is usually located on the driver's side of the engine block, near the front. It might be on a raised surface or directly on the block itself.
* Information: The tag should have a code that starts with "4" or "4ZD" followed by a string of numbers and letters.
* 2.3L Engine: The code will likely begin with "4ZD1."
* 2.6L Engine: The code will likely begin with "4ZC1."
2. VIN Number:
* Location: The VIN (Vehicle Identification Number) is typically found on the driver's side dashboard, near the windshield.
* Decoding: You can use a VIN decoder online to find information about your truck's engine size.
3. Engine Displacement:
* Engine Bay: Look for a sticker or tag on the engine bay that indicates the engine displacement.
* Owner's Manual: Check your owner's manual for specifications.
Important Notes:
* Model: The engine size can vary depending on the specific model of your 1991 Isuzu truck.
* Exact Codes: The engine codes may vary slightly depending on the specific year and model of your truck.
* Professional Help: If you're still unsure, it's best to consult with a qualified mechanic or contact your local Isuzu dealership for verification.
Let me know if you have any more questions!
