You have to learn not to guess at anything on these computer controlled engines.
No, the fuel pressure is not anywhere near 100 psi in the fuel rails. It's more near what you saw on your gage.
Next, the 1409 code is specifically an EGR vacuum regulator fault.
It's either unplugged, open or stuck.
If stuck open it has the EGR open full time and this will cause a drivability issue.
The 1000 code is not a fault code but an indication the system has not passed all 7 system tests.
The code 1000 will clear once all 7 monitors are reset by finding no faults.
The 171 code might be due to the EGR regulator fault (1409).
Clear the 1409 then see what you have after you clear the codes and drive it for a new code history.
Then clear what comes back.
This way there is less confusion about what you have going on.
P0171 System Too Lean (Bank 1)
Freeze Frame for DTC P0171 Fuel System Status Bank One Closed Loop Fuel System Status Bank Two Not Reported Calculated Load 42 %
Coolant Temperature 199 F
Short Term Fuel Trim Bank One -3.90 % Long Term Fuel Trim Bank One 14.82 % Short Term Fuel Trim Bank Two 5.46 % Long Term Fuel Trim Bank Two 7.80 % Engine RPM 1216 r/min Vehicle Speed 30 MPH Enhanced Powertrain
P1409 EGR Vacuum Regulator Solenoid Circuit (See P0403)
P0171 System Too Lean (Bank 1)
P1000 OBD Systems Readiness Test Not Complete Anti-Lock brakes
im using AutoEnginuity OBD2 i have cleared the the codes and did koer test and they will come back time after time
to day i heard a noise after i turned off the truck i could hear a sweak under the hood .
the sweak was comming from the egr line ( white tube ) were it hooks up to the green line at the silanod. i also clean it out very dusty
You have the same info I gave you except an indepth rundown to support the reason for the code 171.
For the vacuum regulator, remove it. Take the round cap off. A spunge filter will be found.
Clean it and spray clean the valve inside to be sure it's free.
The noise you hear is air going back 'into' the EGR to release it. This is why the motor runs so poorly. The EGR is open full time when it should not be.
It's repair time. Do it to it.
I don't know what you brake issue is but if you have no ABS lamp, let that go to last.
Do the work, then lets hear how it ends up.
Have you noticed the first code you gave was 1409.
Now you give 1408.
Both are for EGR operation.
The 1408 is very close to a 401 code.
You have the truck to work on. We cannot tell you exactly what to put your hand on as the hardware trouble.
Possible there is/was more than one issue at the same time.
Work on it to find it, same as anyone else would have to do.
Look up the codes, find out what the test is, that fails.
You have hoses, EVR, EGR, DPFE, and the metal tube between the exhaust manifold and the EGR. All could be a source of a flow failure.
The 1408 code tells you the flow the PCM expected was too low.
The test routine opens the EGR a specified amount by pulsing the EGR to allow flow.
The DPFE measures that flow and reports it to the PCM for comparison to a table. If the value reported is out of limits [for any reason] according to the table match, it's considered a fault and sets the code.
Could be the ports behind the EGR are nearly plugged shut.
There is nothing much more to tell about it.