Remember the "Old Days" when we used a timing light.....it usually collects dust now in the tool box.....but it is useful for TBI systems......shine it on the spray, and you can see the spray better if it has droplets in it.....

Have seen PCM/VCM problems......vehicle run like crap......spray looks ok......but just straying carb cleaner into the throttle body clears up the misfire.....if pressure is ok(usually 9-13 psi), then it could be the computer....

One thing......spray that carb cleaner around the outside of the throttle body, and especially at the base, to see if that gasket is leaking.....this will cause a lean condition....

Id hook a vacuum gage up and check your valvetrain. If the gage fluctuates when its misfiring then the valvetrain is to blame.

Yes it is the tbi. Truck has 153 thousand miles on her and I checked the timing about a year ago and it was dead on. I might just take it down the road to a mechanic and let him give it a listen and see what he thinks