Help ..... juddering on full throttle

[watchman]

A warning light comes on sometimes, and sometimes the juddering continues on any throttle. The only way to correct this is turn off the ignition, and back on again. Once, recently, it went into limp mode.

I read the thread about injectors seals on a 2.0T, but I can't smell petrol.

Is it possible that this is something to do with spark plugs?
Any suggestions?

It has been going on for a few months now.

[diesel dog]

First thing is to get the codes read.