Problems after replacing a fuel pump


#1

We have a 1996 Chevy Blazer. The fuel pump went out, we replaced it ourselves and now have the following problem: The engine starts and initially runs fine. After 10 minutes or so, the engine starts to run rough and loses power. My son, who drives this vehicle, says he can hear what he things is the fuel pump working harder whenever this occurs. He also seems to think that there is a build up of pressure in the system which is causing the problem. Initially, the vehicle would die at this point, but would restart fine and run fine again for a little while. Anyway, my husband found where one of the fuel lines was pinched, so he replaced that. The vehicle doesn’t die now, but continues to have the problem with loss of power. Additional info: a check engine light comes on at times. Our hand held engine diagnostic computer, indicates there is a problem with evaporative system. Any suggestions about how to get this vehicle running smoothly again would be appreciated. We took it to a Chevy garage. They told us we needed to replace the fuel pump. Any suggestions anyone can offer would be appreciated. We really don’t want to replace the fuel pump unless we know there is no other alternative. Thank you.


#2

my dodge has a evaperator canister that has a filter inside. if yours has 1 check to see if the filter is dirty. i replaced the fuel pump im my tank and was recomended to change the evap filter too. hope that helps


#3

Some potential causes could be:
Fuel filter; this should always be replaced with the pump because even a partially clogged filter is a pump killer.
Stuck fuel pressure regulator.
Restriction in the return line to the fuel tank. (Disconnect and try blowing through it)
Fuel pump relay getting hot and breaking down. A chronically dragging fuel pump over the long term draws excess elec. current and over time this can burn the points in the relay. (Remove the plastic cover from the pump relay and eyeball the contact points inside to see if they’re badly burned and pitted)

The pinched fuel line is kind of an odd problem. Was this caused by the pump installation?
Are you sure none of the lines are crossed up at the tank? Usually these are prorietary, but…