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Super Mechanic
Super Mechanic, Master technician
Category: Chevy
Satisfied Customers: 17219
Experience:  29 yrs. exp., ASE master, cert. in G.M. electrical, a/c, susspension, brakes, electronic steering
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2002 chevy silverado 2500: no fuel pressure..harness only 5 volts

Customer Question

have a 2002 chevy silverado 2500 have no fuel pressure checked voltage at harness only 5 volts.
Submitted: 6 years ago.
Category: Chevy
Expert:  Super Mechanic replied 6 years ago.

Hello and welcome to Just, Super mechanic here. About your vehicle.

Which engine is in it?

Which harness did you check?

What color wire did you check?

Customer: replied 6 years ago.

6.0 liter votec

checked single harness connected to fuel pump at tank


purple wire is the only on that gives a reading

had a mobile mechanic come check said fuel pump was bad

Expert:  Super Mechanic replied 6 years ago. will want to have someone turn the key on while you check the voltage at the gray wire. The PCM will only power it for 2 seconds when the key is turned on then it shuts the power off to the fuel pump. Also check the ECM "B" fuse just to be sure.

Most times you can hit the gas tank with a rubber hammer and jarr the pump to start working again.

Customer: replied 6 years ago.
that showed 12 volts also fuse is good ,so is the fuel pump bad want to make sure before i spend a bunch of money.
Expert:  Super Mechanic replied 6 years ago.
If there is 12 volts at the gray wire for 2 seconds when the key is turned on, (or when cranking) and no fuel pressure or the doesn't run then the fuel pump is bad.
I always just check to make sure that the black wire does have a ground. I normally will use it as a ground for the meter when I test the voltage.
Super Mechanic and other Chevy Specialists are ready to help you
Customer: replied 6 years ago.
that also checed out ,thanks
Expert:  Super Mechanic replied 6 years ago.
Your wecome and come again, anytime, thanks