Fuel whins and but engine stars up but it will sometimes stop

ck out these....

https://www.google.com/search?q=1999+Ford+f150+code+p+0171+and+p0174&rlz=1C1CHBD_enUS885US885&oq=1999+Ford+f150+code+p+0171+and+p0174&aqs=chrome..69i57j0i22i30j0i390i650l4.27911j0j4&sourceid=chrome&ie=UTF-8

Best to you

I had a 78 rabbit did the same thing. It was the fuel pump relay. The connector was under size and burnt up. When you star the car on the old Rabbit the pump runs off the ignition switch. Once it starts the relay needs a pulse from the distributor to let it know that the car is running and keep the pump running after it starts. If not the relay times out and pump stops pumping gas. Its for safety so if in a accident and the engine stops the pump wont pour out gas

Whinning Causes
The whining noise you hear coming from the power steering pump is one of three things. The first is more of a loud "hush" than a whine; this is the sound of fluid rushing through the bypass valve when you turn the wheel all the way to one side or the other. Sometimes the bypass valve malfunctions or doesn't open all the way, causing pressure to back up in the pump and cause your engine rpm to drop. The second and third causes result from cavitation -- vacuum pockets created behind the rotor's vane blades as a result of extremely high pump action -- or air in the lines.

As with any no-start or stall problem you will need to figure out if it is a fuel or ignition issue.
The high idle usually means you have a vac leak or a problem with the throttle body or idle air control valve. The control valve is how the computer controls the idle speed.
You'll need to watch the fuel system and spark to see which is being affected when the engine dies.
You might want to hook a test light up to the coil to see if it is loosing voltage for example.

TRY THE FUEL FILTER FIRST IF THE FUEL PUMP WAS GOING BAD IT WOULD STALL AS YOU PUSH ON THE GAS PEDDLE AND PUMPING THE PEDDLE WOULD NOT HELP FUEL INJECTION AND PUMPING THE GAS WILL HAVE NO EFFECT ON THE RUNNING OF THE VEHICAL

hmmm... did he by pass the FUEL FiLTER?

When did u replaced te FUEL FiLTER?

Thats the only thing that troubles the Sentras!

check also the FUEL PUMP, sometimes the pump stop working!

tell me afterwards when u replace the FUEL FiLTER!

I would run another fuel pressure test, I have had fuel pumps bad out of the box..:-(

Fuel pump or fuel filter.

Have you done a back pressure test on it? If you have no idea what I'm talking about, unbolt exhaust at heads or before the catalitic converter/converters. Try starting then driving it then. If that solves your problem, your catalitic converter/converters are clogged.

Mine did that to me about 4 months ago. I started by changing the fuel filter it ran great for a month. but by doing that it released all the pressure off of the fuel pump which then went out. If you run your vehicle below 1/4 tank it starves the fuel pump. The pump needs that fuel because; The fuel is the lubrication for the pump. Running your tank down consistently over a period of time will short the pump out faster.