Can a bad gas cap cause a P0171 code?

Can a bad gas cap cause a P0171 code?

It doesn’t set a code that is false.

Can a bad PCV valve cause P0171?

The most common causes of the P0171 code are vacuum or intake leaks, low fuel pressure, faulty PCV valve, or a faulty MAF sensor. Other things can also cause the P0171 code.

Can a bad 02 sensor cause a P0171 code?

You probably know that the answer the questions is — no! A P0171 or P0174 lean code with an O2 sensor reading lean all the time mean — well, several things. The real problem may not be a bad O2 sensor, but possibly be an engine vacuum leak, low fuel pressure or dirty fuel injectors that are causing the engine run lean.

Can a bad o2 sensor cause a lean code?

So, an oxygen sensor failure can lead to incorrect readings of exhaust gasses. As a result, the faulty sensor can cause, a too rich or too lean condition. Any fuel that leaves the combustion chamber unburned; will enter the exhaust system and light-off when it reaches the catalytic converter.

What causes the p0171 code on a Subaru Forester?

Vacuum Leaks – With the Subaru Forester, one of the most common cause for the P0171 code to show is a vacuum leak. Take a look around and see if you can find the vacuum leak. Here’s a great YouTube video on how to find a vacuum leak. Oxygen Sensor – The P0171 codes is thrown when the oxygen sensor (s) do not register enough oxygen in the exhaust.

What causes the trouble code on a Subaru Forester?

There are many things that can cause the P0171 trouble code on the Subaru Forester. Here are the most common ones. Vacuum Leaks – With the Subaru Forester, one of the most common cause for the P0171 code to show is a vacuum leak. Take a look around and see if you can find the vacuum leak. Here’s a great YouTube video on how to find a vacuum leak.

Why is my p0171 system Lean code not working?

Change the plugs and oil about a month and a half ago and got a maf sensor error and get a P0171 system lean code after resetting the ECU. I’ve been troubleshooting since then but can’t seem to get the P0171 ironed out. The cel only pops at idle and the car runs great through the power band. Here’s what I’ve already done.

What does Bank 1 of p0171 mean?

Code P0171 Definition Bank 1 has too much air or not enough fuel. What Does P0171 Mean? Combustion engines run most efficiently when they maintain an air-fuel mixture ratio of 14.7 parts air to 1 part fuel.