Vlad Soare Report post Posted August 30, 2020 (edited) Hi, My 2017 hybrid Mondeo started doing something very strange recently. When I brake very hard, it first starts decelerating, then suddenly there's a powerful jerk, then it continues decelerating normally. During normal driving, when I drive smoothly and brake gently until the car comes to a stop, it never happens. It's only hard braking that causes this jerk. And it's really strong, it feels like hitting a sleeping policeman at 40 mph. There's no other symptom. The car works perfectly every time, under all circumstances, except when braking hard. Any ideas what the problem might be? I guess I'll have to go to a Ford dealership anyway, but I'm curious as to what could be wrong. I'd like to be prepared when I get there. ? Thank you. Edited August 30, 2020 by Vlad Soare Quote Share this post Link to post Share on other sites
ElectricFan69 Report post Posted September 23, 2020 How does this compare with ABS pumping action? Wonky ABS could make jerking motion - but those have typically a robust self-test that set a fault code. I'd look for something loose in either brakes or suspension that moves when applying the friction brakes hard. It would need to be something with 'sticktion' that would not allow quick movement to the 'reset' position. Step 1 would be a carefool look at the components for signs of wear or loose components. Quote Share this post Link to post Share on other sites
Vlad Soare Report post Posted September 23, 2020 (edited) It doesn't resemble the ABS action all. On slippery ground, if I brake hard enough to trigger the ABS, it's extremely smooth. I can barely feel some vibrations in the pedal. Whereas this jerk is strong, the whole car shudders. And it's just one time, just one single jerk, after which the car continues to brake as if nothing had happened. When this happens I don't feel anything unusual in the brake pedal. It doesn't feel like the pedal were pushed back. And there's plenty of grip, there's no reason for the ABS to activate at all. Edited September 23, 2020 by Vlad Soare Quote Share this post Link to post Share on other sites
eisbaer Report post Posted September 23, 2020 maybe it is this? Quote Share this post Link to post Share on other sites
MacDonald Report post Posted August 20, 2021 Hard Braking Causes 2018 Hybrid to Jump If I brake hard (especially when going even slightly downhill) the car often lurches or bucks once. It seems like the rear brakes seize up for a second. Could this be due to a glitch in whatever controls the balance between electric and mechanical braking. Quote Share this post Link to post Share on other sites