There isn't a standardized, universally accepted "diagram" in the way some things have a simple picture. However, you can represent this firing order visually in a few ways:
* Numerical Representation: Simply listing the cylinders in firing order: 1-3-4-2.
* Spark Plug Wire Diagram: A diagram showing the spark plug wires numbered according to their connection to the distributor cap (if equipped, some later models may have coil-on-plug). The wires would be connected in the 1-3-4-2 sequence around the cap. You'd need a diagram specific to the 1998 4.0L to show the exact arrangement of the cap itself, as this is engine-specific and varies slightly based on model year and minor revisions within the model year. A shop manual or a reliable online parts resource might have this diagram.
* Cylinder Location Diagram: A diagram showing the engine's cylinders and numerically labelling them. Then, arrows or lines could connect the cylinders in the 1-3-4-2 firing order. Again, you would need an engine diagram for precise cylinder location referencing.
To find a visual diagram: The best place to look would be a repair manual specifically for a 1998 Ford vehicle with the 4.0L engine. Online resources like repair manual websites (often subscription-based) or parts websites (sometimes with diagrams embedded in parts information) may also have the information. Remember to specify the exact year and model of your Ford vehicle to ensure you're getting the right diagram.
