Toyota Repair: acceleration hesitation, 2wd pickup, diagnostic check

Question
I've got a 92 2wd pickup that has a hesitation during acceleration (kind of like a "flat spot").  I've cleaned the intake with carb cleaner and run some injector cleaner thru the gas but it hasn't cured the problem.  Could it be an injector going bad?  How do I check them?

Answer
Not very likely an injector problem, check the basic engine timing it should be about 10 degrees advanced with the diagnostic check connector jumped between terminals E1 and TE1, check to see if the timing advance is working it should increase to about 24 degrees when the engine rpm is increased.