Hard Start Fuel Problem Diagnosis

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… Here are the sure fail tests for the fuel system to
save you time and money.. Take a fuel pressure gauge attach it to the
schraeder valve.. turn the key on and off a few time to build up the
pressure in the system… If you are having starting trouble the pressure
will probably drop as soon as it hits 38 or 40 and the pump turns off it
will probably leak back to zero within a few minutes. Ok now right after
you prime the system pinch off the return line near the tank if the
pressure drop stops it is a bad fuel pressure regulator…. Next pinch off
the feed line if the pressure holds then the leak is before the point
where you pinched the line IE fuel pump check valve..hole in the metal
line on the sending unit caused by it rubbing on the inside of the tank
you should visibly be able to see this if you pull the pump and the
sending unit…(this was my problem) or the pulse dampener which is the
piece between the pump and metal line on the sending unit.. the diphragm
tears.. and last if you pinch both the feed and return line near the tank
and the leak down of the pressure continues then a fuel injector is your
problem.. This is the GM test.. saves time and

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