* 2.3L 4-cylinder: This was a very popular choice.
* 2.9L V6: A more powerful option.
To know for sure which engine is in *a specific* 1988 Ford Ranger, you'd need to check the vehicle's documentation (owner's manual, or the vehicle identification number (VIN) decoding). The engine information is usually found on a sticker under the hood or on the door jamb.