The largest online repair guide library for every car

About us
Contact support
FAQ
Sign up
Sign in

Whistling Noise & Oil Consumption on 2019 A4 - PCV Valve?

0

Mike T. · rep 0 · May 22, 4:30 AM · 1 replies · solved · Question

Vehicle: 2019 Audi A4 2.0T Premium

Hello Audi community,

I'm experiencing some concerning issues with my 2019 Audi A4 2.0T (B9) with around 55,000 miles. For the past few weeks, I've noticed a distinct whistling or squealing noise coming from the engine bay, especially at idle or low RPMs. It's pretty consistent and gets louder when I open the oil filler cap.

On top of that, I seem to be consuming more oil than usual. I've had to top it off a couple of times between oil changes, which wasn't typical before. I've also had a Check Engine Light come on intermittently, but it sometimes goes away on its own.

Could this be a failing PCV (Positive Crankcase Ventilation) valve? I've read that these symptoms are common for PCV issues in these engines. What are the signs, and is this a DIY-friendly repair? Any specific OBD codes I should look for if the CEL comes back on?

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 22, 4:30 AM

0

ClearTheCode admin answer:

Your symptoms strongly suggest a failing PCV (Positive Crankcase Ventilation) valve, also known as the oil separator, in your 2019 Audi A4 2.0T. This is a common failure point on many VAG 2.0T engines.

1. Symptoms of a Failing PCV Valve:

  • Whistling/Squealing Noise: This is a classic symptom. It's caused by excessive vacuum in the crankcase due to a ruptured diaphragm within the PCV valve, pulling air past a seal or gasket. The noise often changes or disappears when the oil filler cap is removed (relieving the vacuum).
  • Increased Oil Consumption: A faulty PCV can allow oil to be drawn into the intake manifold and burned, leading to higher oil consumption.
  • Check Engine Light (CEL): A failing PCV can cause various engine performance issues that trigger the CEL. Common OBD-II codes include:
    • P0507 (Idle Air Control System RPM Higher Than Expected): Due to a vacuum leak.
    • P0171 (System Too Lean Bank 1): Also caused by an unmetered air leak.
    • Other misfire codes (P030x) can also occur if the vacuum leak is severe enough to disrupt combustion.
  • Rough Idle or Stalling: Can result from the vacuum leak.

2. DIY Friendliness:

  • Replacing the PCV valve on the 2.0T engine is generally considered a moderately difficult DIY job. It's accessible on top of the engine, but requires careful removal of hoses, electrical connectors, and sometimes the intake manifold or other components depending on the specific engine variant and year. You'll need basic hand tools, a torque wrench, and possibly new gaskets.

3. When to See a Shop:

  • If you're not comfortable working with engine components, or if you're unsure about diagnosing the issue, it's best to take your A4 to a qualified Audi specialist or dealership. They can accurately diagnose the problem, ensure the correct part is installed, and clear any fault codes. Prolonged driving with a faulty PCV can lead to further engine issues, including oil leaks from seals due to excessive crankcase pressure or vacuum.
Menu

Help & account