BMW Federal Emissions Recall Campaign - Delivery Stop: Replace Coolant Expansion Tank [B170324] The manufacturer's recall remedy replaces a defective, heat-compromised plastic coolant reservoir with an identical plastic component that is subject to the exact same thermal fatigue and catastrophic failure. I had the dealer replace the tank in March 2024 under this recall. This week, however, I noted coolant residue from the horizontal seam of the expansion tank. Furthermore, the dealership's primary diagnostic criteria (a cold pressure test) FAILED to detect severe, ongoing coolant leakage that was actively drowning the fuel injectors, nearly resulting in catastrophic engine failure. I demanded the bulletin be followed by removing the expansion tank based on the visual evidence alone. I further demanded bore scope photos as stated in the recall bulletin. These support the above claims that ALL FOUR injectors are contaminated with gross amounts of coolant which could have led to a catastrophic engine failure. BMW replaced my expansion tank in 2024 when I first bought the car with 13k miles on it with a tank that suffers from exactly the same design flaw. It is therefore no fix at all and all of these cars are all ticking time bombs unless a permanent solution is mandated.
- NHTSA ID
- 11771370
- Incident
- Oct 12, 2026