The EA839 2.9T and 3.0T turbocharged V6 found in B9/B9.5, C8 and 4M chassis Audis has an inherent flaw in the mechanical design of its factory water pump. While premature water pump failure isn't uncommon in many Audi and VW engines (e.g. all EA888 TSI engines), when the EA839 pump fails, it can cause some serious damage to the engine.
These engines have been available in several Audi models since the 2018 model year. Now that these vehicles have been on the road for several years, we're starting to see water pump failures in both of our professional service centers all the time. Unfortunately, with the EA839 engine, it's no longer a matter of if your vehicle's water pump will fail, it's a matter of when.
Vehicles Covered
- 2018-2024 B9/B9.5 S4 3.0T
- 2018-2024 B9/B9.5 S5 3.0T
- 2018-2024 B9/B9.5 RS5 2.9T
- 2018-2024 B9/B9.5 SQ5 3.0T
- 2019+ C8 A6 3.0T
- 2019+ C8 A7 3.0T
- 2019+ C8 S6 2.9T
- 2019+ C8 S7 2.9T
- 2018+ D5 A8 3.0T
- 2019+ 4M Q7 3.0T
- 2019+ 4M Q8 3.0T
How The Water Pump Fails
When the water pump inevitably fails, it will start to leak coolant. On most other engines, leaking a little coolant isn't a huge deal. Also, with most other leaky water pumps, you can typically just make sure your coolant is topped off and drive the car until you can get the water pump replaced. Unfortunately, in the case of the EA839 water pump, when it fails, it likes to leaks internally.
This is a big issue because the EA839 water pump uses vacuum to operate a slide valve that controls the actuation of the pump impeller. Vacuum is applied via a solenoid valve to deactivate the water pump. Once the engine gets up to operating temperature, the vacuum solenoid valve turns off the flow of vacuum so that the pump is activated.
This function exists so that the engine can more quickly get up to temperature more quickly when it's cold (this is why you have heat inside your cabin very quickly in the winter). Unfortunately, when the water pump starts to leak coolant internally, the coolant is drawn into the vacuum system of the engine. This migrating coolant can quickly start to make its way into other areas of the engine where coolant should not be present. If a sufficient amount of coolant is drawn into the vacuum system, serious damage to the engine can occur.
Once the pump starts to fail, time may not be on your side. Failure to replace it quickly can lead to catastrophic engine damage. If you start to see any of the signs below, you need to have the pump replaced immediately.
Common EA839 Water Pump Failure Signs
The most common sign is a visible loss of coolant in the overflow reservoir. Once it drops below a certain point, you will receive a warning message on your dashboard.
You may also get a P0299 CEL and the resulting "Drivetrain Malfunction" message on your dashboard due to coolant migrating into the vacuum solenoid valve.
You can also inspect the area on the front of the engine block or the bank one (left side) engine head to see if there is any coolant build-up or residue in that area.
Used Vehicle Sidenote
If you purchased a used or certified pre-owned Audi equipped with an EA839 3.0T or 2.9T engine, you might be wondering if the water pump has already been replaced. The good news is that it's not difficult to identify the old pump. The new pump uses a 6 bolt pulley, while the old, defective pump uses a 4 bolt pulley. You can see the pulley on the front of the engine.
Here's what the old pulley looks like:
What's the Fix?
Audi has developed a new version of the water pump that fixes the internal leaking issue. However, several other parts, gaskets and seals should also be replaced as well. Due to the coolant migration, other components such as the vacuum solenoid valve and the coolant bypass valve may also require replacement.
Fortunately, based on the repairs we've performed in both of our professional service centers, we've created a kit that includes all of the parts necessary when performing an EA839 water pump replacement service. Additionally, we also stock other the other parts that commonly fail along with the pump that should be replaced at the same time.
- Audi EA839 3.0T/2.9T Water Pump Service Kit
- Audi EA839 3.0T/2.9T Vacuum Solenoid Valve
- Audi B9/C7/4M/D5 3.0T/2.9T Coolant Shut Off Valve
If you don't fancy yourself the DIY type, or if this looks to be a bigger job than what you'd like to tackle on your own and you live in the DMV area, please feel free to set up an appointment at one of our professional service centers. If you would like an estimate to perform this repair before setting up an appointment, please feel free to contact us.