Fiesta ABS Light Vibration

Woah, that sounds rough. I've got a Fiesta too. Had a similar thing happen with the tire pressure warning light a while back. Did you actually check the tire pressure with a gauge, or just eyeball it? And when you say vibrating, is it constant or only at certain speeds? Mine was at its worst above 50mph...

Yeah, checked the pressures with a proper gauge, all inflated to the correct PSI. The vibration is pretty constant, gets worse the faster I go, but it's there even at low speeds. You think it was definitely tire-related for you, even with the ABS light on?

Well, for me it turned out the valve was defective. The pressure loss was really slow, so it was hard to detect at first. Got the light, the shaking (though maybe not as severe as yours, now that I think about it), and the weird steering feel. With the ABS light also on, honestly, it sounds like something's definitely gone wrong. I'd get it to a workshop ASAP if I were you. Too much weirdness going on at once, it's beyond my capabilities.

Appreciate the insight. Ended up taking it to the shop as you suggested, and you were spot on – defective valve! New valve, balance, and alignment later, it's all sorted. Cost me about 280€, but worth it for the peace of mind. Thanks again!