Common questions

What is the testing range for fuel pressure?

What is the testing range for fuel pressure?

In general, most vehicles’ fuel pressure range is between 40 – 80 psi.

What should the fuel pressure be on a GM 93 Blazer?

This is the procedure for checking for an internal fuel leak on your 1st gen GM 4.3V6 with the CPI engine in it. This is my 93 Blazer in the test. Fuel Pressure should be 58-62 psi, and it should hold that pressure, and hold it when turned off as well. I have a leak inside my upper intake as I show you in the video.

What does 0 psi mean on fuel gauge?

CASE 2: The fuel pressure gauge’s needle DID drop down to 0 PSI immediately after the Key was turned to the Off position: This tells you that there is something leaking inside the plenum. More than likely, it’ll be the fuel pressure regulator, to make sure go to: TEST 2.

What happens when the fuel injector starts leaking?

So, when the fuel pressure regulator (or a fuel injector) is leaking, the fuel pressure will drop down to 0 PSI as soon as you turn the engine off (and if this happens, then you know that you have a problem). Therefore, very first thing you need to do is a fuel pressure leak down test with a fuel pressure gauge.

What should the fuel pump pressure be to start the engine?

The fuel pump produces much more than just 50 PSI of course but the bare minimum the engine needs to start is 50 PSI. Anything less and it will crank for ever before it starts or not start at all. So, the very first thing you need to do is to verify that the fuel pump is delivering at least 50 PSI of fuel pressure while the engine is cranking.

CASE 2: The fuel pressure gauge’s needle DID drop down to 0 PSI immediately after the Key was turned to the Off position: This tells you that there is something leaking inside the plenum. More than likely, it’ll be the fuel pressure regulator, to make sure go to: TEST 2.

Can a bad fuel pressure regulator cause a misfire?

There are also many causes of engine misfires. It can be a problem in the spark plug or the ignition coil. A fuel injector problem can also cause engine misfires. It is also one of the symptoms of a bad fuel pressure regulator. A problem with this device can lead to low fuel pressure.

How do you install a fuel pressure gauge?

Alright, here are the steps: Connect your fuel pressure gauge to the Schrader valve (see photo above). Before you do, place rags under and around the Schrader valve (as a safety precaution, since fuel will leak when you install the fuel pressure gauge). Activate the fuel pump to pressurize the line.

What should I do if my fuel gauge is leaking?

If the gauge is leaking, you’ll need to tighten it some more and recheck. Now that you have verified that the fuel pressure gauge is not leaking, crank the engine. If the engine starts, have him (or her) turn it off. Observe the fuel pressure gauge’s needle, as soon as you turn off the engine.

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Ruth Doyle