Yes, it can indicate several other problems, but 99 times out of 100, you've got unmetered air getting into the engine after the mass air sensor.

Given that it's a 4.2 liter, I'd lean towards intake gaskets and bolts. If you have access to a scan tool that can display fuel trims, try spraying carb cleaner around the intake while watching your fuel trims. If they suddenly go negative after the carb cleaner treatment, there's your leak. You may be able to notice a running change in the engine when this happens as well.

 

I'm using an Air Hog filter - probably dropped a little more than I should on it. Why do you ask?

Thanks for the info, guys. I will probe around the intake a bit and see if I find any leaks.

 

If you have one that needs to be oiled(like most K&N filters), it increases the chance of your MAF being compromised. It's easy to overdoit thru the oiling procedure.