Hesitation under heavy acceleration: 1st gear @ 20mph, 2nd gear @ 30mph, accelerates nicely to these points, then abruptly hesitates as if 'bogging' down. Have rebuilt throttle body, replace

SOURCE: 2000 Sonoma hesitation at between 1500 and 2000 RPM

You may have got a slug of water in the gas, try some additive and see if it will clear up. If it dosent best do a fuel pressure test, i don't know why but pumps have been known to go out just after a fill up.

SOURCE: 1987 Chevy Suburban 350 2wd not starting or running right

What size engine do you have in it? And, how many miles on it?? Well, I guess it really doesn't matter. At first thought it sounds like you are experienceing a fuel problem, and changing the throttlebody didn't solve your problem. I would start by looking and checking my fuel delivery system. The fact that you had to spray gas into the throttlebody tells me that fuel is not getting there. I would start with the least expensive thing to fix first. Check your gas filters. These are often , OFTEN, overlooked as a sorce of problems, and are rarely changed and often overlooked, and are the problem alot of the time. If that dosen't cure your problem check your fuel pump. Make sure it is delivering the proper pressure. I would bet your problem would be solved, but if it's not then next I would check the electrical components of your fuel system.

SOURCE: my son's gmc 4.3l hesitates upon acceleration. I

do you have any check engine lights on? If you do, that is the first thing I would have checked. It does sound like plugged EGR, vacuum leak, or bad TPS

SOURCE: When accelerating, primarily in lower

I would check fuelpump pressure as I have encountered same symptoms as you desscribed in your complaint.aaaaaaaaaaaaaaAlso check for vacuum leaks while your at it