Just bought a 94 B2300. Engine seems strong yet there it is missing and hesitating most noticably at low speed. Change plugs and ran some injector cleaner through a tank of gas with no results. Any ideas?

How did EACH plug look when you took them out? Any combustion or ignition problem should evident in the plugs.

Could be a bunch of things but most common things to look for:

Clogged Air filter
Clogged fuel filter
Low fuel pressure
Spark Plugs (which have been changed)
Spark plug wires
Ignition timing problem
Plugged injector
Water in fuel
Throttle Position Sensor

Its very easy for a small piece of dirt to get into an injector and skrew up how it atomizes the fuel, most of the time this requires some sort of dissassembly to clean/fix. Injector cleaner mainly breaks down chemical deposits that may have accumulated.

Thanks for the advice. I also saw on another post that there may be a small vaccum leak. I will check all of these things out as best I can. Thanks again.