However, a generally accepted guideline is that individual cylinders should be within 10% of each other, and ideally above 100 psi (pounds per square inch). Some sources might suggest a minimum of 120-130 psi per cylinder, but even then, the relative consistency across all cylinders is more critical than hitting a specific number.
To find a more precise specification:
* Consult your owner's manual: This is the best place to start. It might list a compression range.
* Check a Ford repair manual specific to your year and engine: These manuals often provide detailed specifications and diagnostic information. (Haynes and Chilton are popular brands.)
* Search online forums: Websites and forums dedicated to Ford Explorers or the 4.0L Cologne V6 might have discussions about typical compression readings. Remember to specify your engine size when searching.
Important Note: Always perform a compression test according to the instructions provided in a reliable repair manual to ensure accurate and safe results. Low compression in one or more cylinders could indicate serious engine problems requiring attention.
