Not starting, codes P0171, P0461, P0463 and P0339

Hi and thanks for using 2CarPros.
171 lean fuel mixture
339 Camshaft position sensor intermittent
461 Fuel level sensor performance
463 Fuel level sensor performance high
___________________________________________

What does that all mean? Well, 171 indicates you are getting too much air into the engine and not enough fuel. Often times that is caused by a vacuum leak or a weak fuel pump.

The 339 is indicating there is an intermittent problem with the camshaft position sensor, but that shouldn't prevent it from starting.

Now, the ones of interest are the fuel level sensor codes. The fuel level sensor is plugged in above the fuel tank at what is called a sending unit. The plug provides power to both the pump and the level sensor. Not always, but most times, the codes you indicated (461 463) are related to a corrosion problem or bad connect. If the level sensor is not getting a good connection, there is a good chance the pump isn't either. That could lead to low fuel pressure (P0171) and finally a no start.

With that in mind, the first thing I need you to check is fuel pump pressure. First, here is a link that shows in general how to check fuel pressure. You will need a fuel pressure gauge, but most parts stores will lend or rent one to you.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Here are the directions specific to your vehicle for testing fuel pressure. The manufacturer's fuel pressure specifications are included in these directions. Also, the attached picture shows how the fuel pressure gauge is attached to the fuel rail at the top of the engine. Don't be intimidated with the directions. If you have questions, you can ask and I'll do my best to help.

_______________________

FUEL PUMP PRESSURE TEST
Use this test in conjunction with the Fuel Pump Capacity Test, Fuel Pressure Leak Down Test and Fuel Pump Amperage Test found elsewhere in this group.

Check Valve Operation: The electric fuel pump outlet contains a one-way check valve to prevent fuel flow back into the tank and to maintain fuel supply line pressure (engine warm) when pump is not operational. It is also used to keep the fuel supply line full of gasoline when pump is not operational. After the vehicle has cooled down, fuel pressure may drop to 0 psi (cold fluid contracts), but liquid gasoline will remain in fuel supply line between the check valve and fuel injectors. Fuel pressure that has dropped to 0 psi on a cooled down vehicle (engine OFF) is a normal condition. When the electric fuel pump is activated, fuel pressure should immediately (1-2 seconds) rise to specification.

All fuel systems are equipped with a fuel tank module mounted, combination fuel filter/fuel pressure regulator. The fuel pressure regulator is not controlled by engine vacuum.

Warning: the fuel system is under constant fuel pressure even with the engine off. Before disconnecting fuel line at fuel rail, this pressure must be released. Refer to the fuel system pressure release procedure.

Fig. 7 Fuel Pressure Test Gauge (Typical Gauge Installation At Test Port)
See pic 1

1. Remove protective cap at fuel rail test port. Connect the 0-414 kPa (0-60 psi) fuel pressure gauge (from gauge set 5069) to test port pressure fitting on fuel rail (Fig. 7). The DRB III Scan Tool along with the PEP module, the 500 psi pressure transducer, and the transducer-to-test port adapter may also be used in place of the fuel pressure gauge.
2. Start and warm engine and note pressure gauge reading. Fuel pressure should be 339 kPa ± 34 kPa (49.2 psi ± 5 psi) at idle.
3. If engine runs, but pressure is below 44.2 psi, check for a kinked fuel supply line somewhere between fuel rail and fuel pump module. If line is not kinked, but specifications for either the Fuel Pump Capacity, Fuel Pump Amperage or Fuel Pressure Leak Down Tests were not met, replace fuel pump module assembly. Refer to Fuel Pump Module Removal/Installation.
4. If operating pressure is above 54.2 psi, electric fuel pump is OK, but fuel pressure regulator is defective. Replace fuel filter/fuel pressure regulator. Refer to Fuel Filter/Fuel Pressure Regulator Removal/Installation for more information.
5. Install protective cap to fuel rail test port.

___________________

When I diagnose problems with multiple codes, such as you have, I try to find a link between them. In this case, I suspect there is a poor connection at the fuel pump and level sensor. If I am right, you will find either no pressure or low pressure when you check. We need to get the engine running again to confirm what is happening with the camshaft position sensor. So, lets focus on that first.

Feel free to ask questions if you need help.

Let me know what you find.

Take care,

Joe

No problem. Happy to help. Let me know what you find or if you have other questions.

Take care,
Joe