I have a 1989 S10 Blazer 4.3 TBI with maybe 105k miles on it, I just gave it a nice tune up which includes K&N air filter, new cap/rotor, spark plugs, spark plug wires, vacuum wires, EGR, O2 Sensor, Hollowed out the cat and got a thrush muffler fresh oil and tranny fluid & filter, now when I give it a little gas it seems to stumble, bog down hiccup whatever you want to call it, I ran it on my buddies scanner and no codes came up but it said I was running at about 480-550 rpms at an idle sometimes it'll drop down to about 420-430 I swapped my buddies IAK (spelling) and Throttle poistion sensor in my truck and they didn't help either, frankly besides it being the fuel injectors or inside the T.B.I I have no idea what else it could be, any help would be greatly appreciated.

Thanks,
Phil

 

most likely fuel delivery system, pump, regulator, injector etc not sure tho

 

Update: I bought the TBI rebuild kit for $37 and placed all the seals/gaskets of the top half, I do notice a difference in throttle response and it doesn't run rich anymore yet it still bogs down at about 2-2.5k RPMs in any gear.... I have no clue anymore lol

 

If your only running to 2500RPM before it bogs you have a Vacuum Advance problems

 

Already put all new vacuum wires in about a month or so ago.