well i just bought this 95 blazer and all seemed well until the fuel pump went bad. so i had a new one installed and it ran great for a day or so but now its stallling again. the engine does not seem like its recieving fuel. also when pressure builds up in the tank gas leaks out of the hose by the gas cap. the truck ran fine with the gas cap off though? could it be another bad pump even though its new? or maybe an electrical problem? or a vent line issue?
please help

 

To see if it is the fuel pump first check if the fuel pump is even running(you should be able to hear it, a higher pitched wine almost but not extremely loud) Next check how much fuel PSI you have at the engine. There are service ports on the feul line in the engine compartment that you can screw on a fuel psi gauge to. For the other problem, that sounds like an emissions problem, possibly a plugged charcoal canister or vent lines to it?

 

has the fuel filter been changed since the pump? and what brand pump was installed? The fuel filter should be in the frame on the drivers side under the area of the drivers seat...

 

the mechanic whos a family friend said that he replaced the filter with the pump. he just called me today to tell me he replaced the vacumn lines on it as well. but he said that if it doesnt solve the issue of it stalling it could either be the fuel regulator or the fuel injector? that sound about right?