So i bought this 88 k5 has a 305 tbi around 16,000 since rebuild of engine and tranny. I put a new fuel and air filter, in tank fuel pump, plugs, and wires and the the powers just not there when you get on it. No power going up hill or when you push it to the floor. Using gas like crazy. It has the original cat on it never had any exaust work could a clogged cat cause this?

 

I would check the fuel psi first to see what it is. but i know the TBI's are known for fuel regulator issues because the regulator is on top of the injectors in the throttle body. also i would check the lines since the tank was out of it. just to make sure the are not kinked or anything. Did the truck run good before this work was done?

 

I would check the regulator and on top of that I would deffinitly get the cat checked out, if you have a bad cat it will create the same problems!!

 

I bought it and was told the fuel pump was out so i replaced it and it runs great at idle and i still drive it but it boggs. I havent checked the psi yes i will check the lines but it seems to me its getting to much gas but im not sure. i took the regulatore apart and i didnt notice anything that looked bad?

 

Does the exaust smell rich? those regulators are a pain the never take to rebuilding they always seem to bypass no mater what you do to them i think the injector and reg assembly you can get from napa fairly cheep if i remember. its been awile since i have delt with one. or you can yard the intake and get a carb and a used HEI distrib and go old school!. but if you suspect excess fuel or a bad head gasket i would change the cat anyway!