Hey Guys,
I thought I posted this question, but can't find it.
Have any of you guys heard of fuel pressure problems with the 04 Titans? Can anyone Tell me how to check it? I looked for a valve on the fuel rail but didn't really dig for it. I have a Gage but don't know if I have the right adapter. My truck doesn't always respond the same with the same throttle position. You know how your truck feels, and sometimes I make a turn and give it the usual amount of gas and it just don't go the same. Also some mornings when I start it I here a buzzing sound from the fuel tank. I'm hoping that the poor fuel mileage is because of low pressure. I really don't trust the dealer to find this problem, because the first time they changed my oil, they didn't even change the oil filter.
James

It's not as easy as you would think it should be, but here it is. This is cut and pasted from the service manual.

1. Remove fuel pump fuse located in IPDM E/R.
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel
pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
FUEL PRESSURE CHECK
CAUTION:

Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.

Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel
pressure cannot be completely released because A60 models do not have fuel return system.

Be careful not to scratch or get the fuel hose connection area dirty when servicing, so that the
quick connector o-ring maintains sealability.

Use Fuel Pressure Gauge Kit J-44321 and Fuel Pressure Adapter J-44321-6 to check fuel pressure.

Do not perform fuel pressure check with electrical system operating (i.e. lights, rear defog, A/C,
etc.). Fuel pressure gauge may indicate false readings due to varying engine loads and changes in
manifold vacuum.
1. Release fuel pressure to zero. Refer to EC-46, "FUEL PRESSURE RELEASE" .
2. Remove engine cover.
3. Remove fuel hose using Quick Connector Release J-45488.
Refer to EM-29, "FUEL INJECTOR AND FUEL TUBE" .

Do not twist or kink fuel hose because it is plastic hose.

Do not remove fuel hose from quick connector.

Keep fuel hose connections clean.
4. Install Fuel Pressure Adapter J-44321-6 and Fuel Pressure
Gauge (from kit J-44321) as shown in figure.

Do not distort or bend fuel rail tube when installing fuel pressure
gauge adapter.

When reconnecting fuel hose, check the original fuel hose for
damage and abnormality.
5. Turn ignition switch ON (reactivate fuel pump), and check for
fuel leakage.
6. Start engine and check for fuel leakage.
7. Read the indication of fuel pressure gauge.

During fuel pressure check, check for fuel leakage from fuel
connection every 3 minutes.
8. If result is unsatisfactory, go to next step.
9. Check the following.

Fuel hoses and fuel tubes for clogging

Fuel filter for clogging

Fuel pump

Fuel pressure regulator for clogging
If OK, replace fuel pressure regulator.
If NG, repair or replace.
10. Before disconnecting Fuel Pressure Gauge and Fuel Pressure Adapter J-44321-6, release fuel pressure
to zero. Refer to EC-46, "FUEL PRESSURE RELEASE"