You can't test it. That's why the tech at the dealer here keeps a used spare on his bench - test by substitution. You could pull yours and inspect it very carefully for carbon tracking and cracks, that's about it - unless you have some expensive diagnostic equipment. Even that wouldn't be conclusive.

Maybe you can get a used one out of a junkyard cheap. Just inspect it carefully and clean it up.

 

There is a procedure to test it with an ohm reader in my Haynes manual but like I said, I found it confusingly worded. Doing a little more research, I'm wondering if I may have been mistaking lifter ticking for a miss...or coul be a vacuum leak...or bad injectors...tick tick tick tick... it makes me crazy, lol. Guess I'll just live with it. I may go ahead and replace the coil pack just for giggles as my truck does feel kind of tired and seems like they're regular maintenance items on these trucks. Thanks!

 

Oh, and for the record, I did end up replacing my coil pack and no difference.

 

The ticking is pretty normal for these motors. Mine has ticked as long as I've had it, almost 5 yrs. From what I've researched its prolly the injectors making the ticking sound. Other thing that might cause the ticking is an exhaust leak where the headers meet the exhaust manifold. Over time the bolts might come loose and the header doesn't make a perfect seal.

 

Yeah, I've read a whole bunch of ticking threads on here and injectors seems to be a common consensus. Mine has ticked for years too. Didn't bother me too much, but she is starting to feel sluggish more often than not these days. I'm kind of tired of throwing parts into her with no results. 163K miles and counting though!