I originally changed all 4 injectors. But anyway, i followed your advice and bubble leak tested the injectors and found that 3 of them were leaking. So I removed the 3 and cleaned and lubricated the o rings and cleaned the internal bores the best I could and re installed them. No leaks now. Thanks for the tip on the bubble leak test.

My reason for changing the injectors is because I have been having to spray ether in the intake to get it to start for a few months now. The injector change out did not solve the problem.

Before changing the injectors i removed the fuel tank , cleaned it out, new hoses, installed a new lift pump and installed an electric lift pump from the fuel tank to the lift pump.

Besides the main fuel pump what else could it be?