Oil Starved Turbochargers Cause Sudden Engine Stalls

Key Points

  • The twin turbochargers in Audi's 4.0L V8 engine can become oil-starved and fail.
  • An oil screen deep in the valley of the engine can become clogged and limit flow to the turbochargers.
  • A federal investigation was opened after a spike in complaints about engines suddenly stalling in the middle of the road.
Gray RS 7 Sportback on a concrete dock near the water
Posted on
Author
Scott McCracken
Tagged
#engine #investigation

The twin-turbochargers in Audi's 4.0L V8 engine can become starved of oil because of a clogged filter. This can cause strange acceleration noises, difficulty starting the engine, or sudden stalls.

An oil screen deep in the valley of the engine filters the oil before it goes to the turbochargers. The screen can become clogged in large part due to the filter's location and the difficulty of keeping it serviced.

The turbochargers are doomed once the oil stops flowing.

Federal Investigation Opened

The National Highway Traffic Safety Administration (NHTSA) opened an investigation into turbocharger failures following complaints from owners who had their engines suddenly stall without any warning.

The investigation covers:

  • 2013-2016 A8
  • 2013-2016 S6
  • 2013-2016 S7
  • 2013-2016 S8
  • 2013-2016 RS7

Damaged Turbocharger Service Bulletin (TSB)

Audi released TSB 2044640 titled Engine difficult to start, turbocharger damaged, V8 4.0TFSI addressing the complaints about the engine being difficult to start, making unusual noises during acceleration, or has reduced performance.

In addition to the models listed in the investigation, the service bulletin also covers the 2013-2016 RS6.

Technicians are advised to look for the following damage:

  • Damage to the turbocharger impeller fins
  • Increased free play on the turbocharger impeller shaft
  • Broken turbocharger impeller shaft

Finding where the damage comes from

Audi says damage to the turbocharger is rarely a result of the actual part failing, but rather the result of poor service, an incorrectly fitted oil filter element, leaks in the intake tract allowing debris into the charger, or a poor oil supply to the turbocharger.


Header photo by Remy Lovesy on Unsplash

Generations Where This Problem Has Been Reported

This problem has popped up in the following Audi generations.

Most years within a generation share the same parts and manufacturing process. You can also expect them to share the same problems. So while it may not be a problem in every year yet, it's worth looking out for.

  1. 3rd Generation A8

    Years
    2011–2018
    Reliability
    18th of 39
    PainRank
    0.97
    Complaints
    16
    Continue
  2. 4th Generation S6

    Years
    2011–2018
    Reliability
    6th of 39
    PainRank
    0.1
    Complaints
    1
    Continue Front 3/4 view of a S6
  3. 1st Generation S7

    Years
    2013–2017
    Reliability
    6th of 39
    PainRank
    N/A
    Complaints
    0
    Continue Front 3/4 view of a S7
  4. 3rd Generation S8

    Years
    2010–2018
    Reliability
    4th of 39
    PainRank
    0.07
    Complaints
    2
    Continue

What Owners Say About This Problem

Vehicle was in motion when it started shaking roughly. The car stalled and wouldn't turn back on. I had it towed home and was able to diagnose seized turbo compressors. Replaced the turbos which fixed the problem but at an enormous cost.

The turbos on the car both broke at the intermediate shaft before 75,000 miles. The car was cruising on the freeway, and the moment I slowed down to take the exit, the car lost power and shut down. I had to make an emergency stop on the side of the exit with little to no room to pull over.

OK, Now What?

Maybe you've experienced this problem. Maybe you're concerned you will soon. Whatever the reason, here's a handful of things you can do to make sure it gets the attention it deserves.

  1. File Your Complaint

    CarComplaints.com is a free site dedicated to uncovering problem trends and informing owners about potential issues with their cars. Major class action law firms use this data when researching cases.

    Add a Complaint
  2. Notify CAS

    The Center for Auto Safety (CAS) is a pro-consumer organization that researches auto safety issues & often compels the US government to do the right thing through lobbying & lawsuits.

    Notify The CAS
  3. Report a Safety Concern

    The National Highway Traffic Safety Administration (NHTSA) is the US agency with the authority to conduct vehicle defect investigations & force recalls. Their focus is on safety-related issues.

    Report to NHTSA