For about 6 months my car has been juddering intermittently.
Happens once in maybe every 10 car journeys and can kick in at any time. Driving normally one moment and then it feels like there's a pull back and starts juddering, particularly in 1st and 2nd gear.
Its also happened a few times when travelling at a steady speed on the motorway - the pull back that is. It doesn't judder at higher revs.
I have noticed a strong smell of diesel in the car when it happens.
It'll last for a few journeys maybe and then run smoothly again for a while.
I tried some DPF cleaner which didn't solve it but otherwise I don't know what the problem could be.