Quote Originally Posted by 85cj7 View Post
replaced the #4 plug and no change in behavior. Still idles crappy and vibrates until 2k before smoothing out. Also can hear pinging/ticking occuring on the passanger side, so cylinders 1-4. Could a spark plug blowing up like that damage the coil? I don't want to drop $50 on a coil to find out it isn't the culprit. Any suggestions? A code reader would definently come in handy right about now.
Does that truck have an icm of some sort? That's the first thing that comes to mind for me when I hear about misfires at low rpms that smooth out at higher ones. Coil is also a good bet...they can go out at the lower RPMs (lower voltages) but still work fine at higher RPMs...I think