I've been researching cracked head symptoms on here, and I have one question I really couldn't get answered. Will a cracked head always cause a check engine light, or can it be a slight enough miss that it isn't tripping the light?

I'm asking more out of curiosity than anything else. I just want to be prepared for what sounds like the inevitable. My truck runs well (though it does need a tune up) and no lights are on. I'm just paranoid about it because I've had head issues on other vehicles (non dodge) and it's always a lot of work and often expensive. This is my first vehicle with iron heads. I'm used to aluminum heads and steel blocks (and in some cases aluminum blocks too).

I plan on doing the cap, rotor, nice Taylor or MSD wires, nice plugs (not sure on the best plug for these trucks yet), and probably an MSD 6a coil since my coil looks original. yes, I will be checking the plenum too. I haven't had a chance to do it yet. I would hope after 170k though, a previous owner would have been smart enough to do it already .