I am planning on buying an 86 iroc z...it has an older 400ci engine..the guy says that it is using tto much fuel and is not sure of the reason...so far he has rebuilt the carb and put these new parts, msd coil, new plugs, wires, cap, rotor ,fuel pump, fuel lines. anyone know what else could be wrong?

 

Is anything comeing out the exhaust?

 

the guy who rebuilt the carb prolly didnt adjust the jets properly. fidle with them a bit and then see.

 

Yeah, your problem isits a 400....not known for their fuel economy.

Seriously, whats it doing?

 

the guy says that its not bad problem....its his daily driver...and nothing is coming out the exhaust

 

punch it and see if any smoke comes out. if its grey or blackish theres too much gas and not enough air. or try checking the fuel pump