ok so ive got an 89 burban (i know i know, but this site seems to be the best for info on tbi) and when cruising at about mid throttle it sometimes has a slight hesitation (feels like that first misfire you get when running out of gas)... i cant figure out any specific things that make it happen yet as it doesnt happen continuously.. has anyone ever felt this? its a 350tbi with a th400.. i've never really worked with tbi so im just wondering what you guys might think..

 

1988 K1500. Misfired at highway speed. Got worse as time went on. (Several months) Misfired at progressively lower speeds. Eventually stalled at idle. Took maybe 6 months to progress that far.

"Fix" was to replace distributor main shaft (or install replacement distributor)

 

Check basics, make sure your ignition is up to par. New spark plugs, wires aren't burnt. Cap and rotor are not corroded beyond optimal use. You can pop off the air cleaner and fire up the motor and look for a nice cone shaped fuel spray while your at it.