I was wondering if the injectors leak but the fuel pump is ok, will the fuel line leak down back to the fuel tank. Doesn't seem that it would. Does the fuel pump have a check valve? If it is ok then the fuel shouldn't leak back to the tank.

My question revolves around people having trouble starting the car and cranking long. I know the fuel pump relay could be not pulling in and the oil pressure switch will pull in the pump but this is a discussion about the pump, injectors and regulator.

(If the pump has a check valve)? and it is ok, could the injectors or the regulator (with a hole in it) still cause the line to leak back to the tank?

I don't see how?

Explain please

 

As far as I know, there is no 'check valve' in the fuel pump/tank, but if any fuel went back to the tank, it would be from the designated return line. If the injectors leaked, wouldn't they leak into the heads?

 

I belive the fuel pump does have a check valve.....and for slow cranking that is fuel related thats usually the problem.