BMW X5: M50d N57S 3.0L quad/tri-turbo boost and actuator failure
M50d N57S 3.0L quad/tri-turbo boost and actuator failure is a common engine fault on the BMW X5 on the 2013–2018 cars, and we rate it major. Putting it right costs $2,500 to $9,000 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 41 documented faults on the BMW X5.
- Vehicle
- BMW X5
- Engine
- N57
- Years
- 2013–2018
- Fuel
- diesel
- System
- Engine
What you are looking at
No photograph available
What goes wrong
The F15 X5 M50d runs the range-topping N57S with three (marketed by BMW as multi-stage 'quad-turbo' on some literature) turbochargers on one 3.0-litre six, giving huge output but a complex boost system with several actuators and control flaps. Soot and age seize the actuators and clog the vanes, producing intermittent low boost, limp mode and costly diagnosis, and the highly-stressed engine works its timing chain harder too. Repairs are dear because the turbos are staged and BMW bundles actuators with turbo assemblies.
What you would notice
- Intermittent low boost / limp mode
- Full power only after an ignition off-on cycle
- Boost-pressure and turbo-actuator fault codes
- Lag or flat spots across the rev range
How to check it
Where to look. Multi-stage turbochargers and actuators on the exhaust side of the engine
On the drive, accelerate firmly from low and high revs to confirm all turbo stages deliver smooth boost with no limp mode.
Scan for boost/actuator codes.
Ask whether any turbo or actuator has been replaced and whether the timing chain has been checked given the high output.
What it costs to put right
$2,500 to $9,000 at New Zealand independent workshop rates. That is for this job on its own, not for the car.
Ask the seller
- “Does it ever lose boost or go into limp mode?”
- “Have any of the staged turbos or actuators been replaced?”
Now check the BMW X5 you are actually looking at
Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.
Where this comes from
- ECU Testing BMW turbo actuator problem page
- Santjer Performance N57 turbo upgrade / failure notes
- BimmerFest N57 multi-turbo actuator threads
BMW X5 buyer questions
Is m50d n57s 3.0l quad/tri-turbo boost and actuator failure serious on a BMW X5?
We rate it major and common on the BMW X5. The F15 X5 M50d runs the range-topping N57S with three (marketed by BMW as multi-stage 'quad-turbo' on some literature) turbochargers on one 3.0-litre six, giving huge output but a complex boost system with several actuators and control flaps. Soot and age seize the actuators and clog the vanes, producing intermittent low boost, limp mode and costly diagnosis, and the highly-stressed engine works its timing chain harder too. Repairs are dear because the turbos are staged and BMW bundles actuators with turbo assemblies.
How much does it cost to fix on a BMW X5?
$2,500 to $9,000 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.
Which BMW X5 years are affected?
Our research records this fault on the 2013–2018 BMW X5. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.
How do I check for it before I buy?
On the drive, accelerate firmly from low and high revs to confirm all turbo stages deliver smooth boost with no limp mode. Scan for boost/actuator codes. Ask whether any turbo or actuator has been replaced and whether the timing chain has been checked given the high output. Look here: Multi-stage turbochargers and actuators on the exhaust side of the engine