What causes low fuel pressure and p0171 code?

What causes low fuel pressure and p0171 code?

A leaky or faulty EVAP valve can cause a lean mixture. You can often test this valve by blowing through it to see if it’s closed or not when it should. Note: The problem is often at the hose between the intake and fuel pressure regulator, this will cause a low fuel pressure and a triggered P0171 code. 5. Check the fuel pressure

What are the symptoms of a p0171 leak?

What Is The Cause Of P0171? 1 Dirty or faulty mass airflow sensor 2 Vacuum leaks – PCV hoses, vacuum hoses, intake manifold gasket. 3 Weak fuel pump 4 Clogged or dirty fuel injectors 5 Clogged fuel filter 6 Exhaust leak 7 Faulty oxygen sensor 8 Faulty air-fuel ratio sensor

Is there a way to reset the p0171 code?

To clear or reset the P0171 code, you need to use an OBD2 scanner. Remember that just resetting the code will not fix the problem causing it from the beginning, and it will most likely come back again. Founder, owner & main author of Mechanic Base.

What does p0171 mean on a Honda Accord?

To keep the engine running properly, the powertrain control module (PCM) tries to compensate for the lean condition by injecting more fuel to the mixture in an effort to maintain the proper 14.7:1 ratio. When these adjustments become too large, code P0171 is triggered. If playback doesn’t begin shortly, try restarting your device.

What causes the p0171 code on a Ford TSB?

Another Ford TSB for a number of late 90-s Ford vehicles describes a problem with MAF sensor contamination where both codes, P0171 and P0174 would appear together. Problems with the mass air flow (MAF) sensor causing the code P0171 are fairly common in many vehicles.

What does the p0171 code on bank 1 mean?

Code Definition. P0171 – System Too Lean (Bank 1) What does the P0171 code mean? The P0171 code means that the Oxygen (O2) sensor on bank 1 recognized a too lean mixture to correct it. The Oxygen O2 sensors have the ability to correct a fuel mixture of +-15%. If it needs to correct the air-fuel mixture more than that, the P0171 code will be stored.

When does the front O2 sensor Register p0171?

P0171 is triggered when the front O2 sensors recognize a lean mixture. It can both be a short-term lean mixture or a long-term lean mixture. If it’s a short-term lean mixture the fuel mixture is often very lean. If it’s a long-term mixture, it can register the code because of a small notice of lean mixture over time.

What causes the p0171 code on a Pontiac?

The P0171 code could also be caused may be caused by one or more of the following: debris on MAF sensor causing an incorrect reading, improper oil level, low or high fuel pressure or Engine Control Temperature (ECT) Sensor reading inaccurate. There is a factory service bulletin for the following Pontiac models: 2000-2001 Pontiac Transport

What does lean Bank 1 on a Pontiac mean?

P0171 PONTIAC Fuel Trim System Lean Bank 1: Code Meaning, Causes, Symptoms, & Tech Notes P0171 PONTIAC | Fuel Trim System Lean Bank 1 | The Engine Control Module (ECM) controls the air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and

What causes a p0171 fuel trim system Lean Bank 1?

If the problem persists the front oxygen (O2) sensor may need to be replaced. The P0171 code could also be caused may be caused by one or more of the following: debris on MAF sensor causing an incorrect reading, improper oil level, low or high fuel pressure or Engine Control Temperature (ECT) Sensor reading inaccurate.