Fuel Pressure Gauge

repair

#1

I have a 1993 ford taurus 3.8L V6 automatic GL. Can anybody tell me what a “EFI/CFI fuel pressure gauge T80L-9974-b” is and where can I get one? Chilton’s says that you need one of these to relieve the fuel pressure from the “schrader value.”


#2

They are referring to the safest way to relieve fuel pressure. The way that many mechanics relieve fuel pressure is to place a rag around the schrader valve and depress the center of the valve. Fuel can squirt several feet as the fuel pressure releases. Therefore, wear safety goggles, if you do it this way.
Sears, and auto parts stores, have a fuel pressure test gauge which has a tube which leads the fuel into a container. You don’t have to use the particular one the manual names.

If you are troubleshooting the fuel system, use of a fuel pressure test gauge is an excellent idea. One mis-diagnosed fuel pump defect, resulting in replacement of a good fuel pump, will pay for several fuel pressure test gauges.


#3

you understand what a schrader valVe is correct?


#4

If all you need to do is relieve the fuel pressure, you don’t need this special tool. The procedures in the Chilton’s manuals are cribbed from the Ford factory service manual, which is written for techs who would have the special pressure tester lying around.

My favorite method for relieving the fuel pressure is simply to pull the fuse for the fuel pump and then run the car until it dies. Crank it a few more times and you should be good. On some cars you need to take the gas cap off, too, since the pressure in the tank can cause gas to dribble out of whatever you’re taking apart. You can confirm that the pressure is relieved by pushing the pin down on the schrader valve on the fuel rail. (Which, FYI, is the same kind of valve you use to put air in your tires. It might have a little metal cap on it).


#5

A schrader valve is used in tire stems also. Just like a letting the air out of a tire, You can use the back side of tire gauge to relieve the pressure in the fuel line, just use a rag to catch the fuel squirting out. If you are sensitive to gas, you may also want to wear nitril gloves.