159 1.9 JTD Whole car wobbles above 20mph
So, after a few miles of driving, maybe ten minutes, when I accelerate perfectly normally in third or fourth I often, but not always and with varying movement, get a wobble on. When it is bad the whole car feels like it is moving side-to-side with a constant frequency of wobble. You really feel it in your bum. The car tracks straight and true but the body just, well, shimmies, left and right.
Stick her in neutral or de-clutch and it evaporates.
It only seems to happen once we're up to at least 20-25mph and only once we've been motoring for ten minutes or so and doesnt seem to be engine speed related but more road speed.
I first felt it when accelerating from some lights, it wasn't a Traffic-light Grand Prix start, just a brisk move away, but it was very unnerving.
It's not always bad, not a consistent degree of wobble, but once she's in the mood to shimmy, she shimmies. And now I kinda feel like there's background, low level, shimmy going on all the time (after those few minutes). But I'm not convinced that isn't paranoia creeping in.
Any ideas what is causing it? I've loomed around here, found similar but not quite the same stories so thought I'd seek input. My garage do have a theory but I want to see if anyone comes up with similar.