I have a 89 s-10 blazer with a 4.3 tbi and when im pulling a trailor or at full throttle i can smell a fuel smell from under the hood. I have replaced egr vaccum solenoid, map sensor, fuel pump relay(different problem). plugs, wires, cap, rotor,and pcv valve. It runs just fine never has a problem starting idling and has plenty of power. I suspect it could be injectors because i have heard they are problems but i have no clue what is wrong and im tired of my eyes burning. Also the other day when i was being followed by a friend he said everytime i was full throttle black smoke came out. Please give me ur insight because im clueless.

 

Sounds like you have a fuel leak under the hood... Does not sound like it from your description of when you get the smell, but if you are getting a smell of fuel, that is the only explanation. Your truck is obviously going way rich on hard acceleration. It is possible that you have a bad gasket in the throttle body that leaks while under acceleration... I would start with a rebuild of the carb with all new gaskets.

 

Might be an O2 censor

 

I do have a code for an O2 sensor but its an obd 1 system and i didnt think it relyed on it as much as obd 2 did and my throttlebody is dry outside of it but the inside is nasty and i also towed the boyscout trailor again this weekend hence the lack of reply and it just smelled so rich and the smell about killed my gf following behind me

oh and im sry that rich fuel smell doesnt smell like raw fuel , just smells really rich

 

Once in closed loop, the O2 sensor is the main sensor used for determining the injector pulse width. What was the specific code?

 

i dont remember what code it was but i think it was a o2 too lean and a o2 too rich but i cant check it right now because my girlfriend took it to work and she drives semi so it is at her shop i will check the codes on friday and let you know