1999 ford explorer sport firing order diagram?

The firing order for a 1999 Ford Explorer Sport's 4.0L SOHC V6 engine is 1-5-3-6-2-4. There isn't a widely available diagram image specifically for that year, as the firing order remains consistent across many years for that engine. You can find diagrams online generally showing the firing order for the 4.0L SOHC V6, but they will all show the same sequence. Remember to consult your owner's manual for the most definitive information.