I think a "Terraclean" (which, I believe, is just one particular franchise of carbon cleaning company) only clears accumulated oily soot from the inlet tract? If anything, it might actually remove it from the inlet tract and dump it in your DPF, making the problem worse, rather than better?
As others have suggested, a "forced regen" is the next thing to try. You'll need someone with the proper software. Beware, because a lot of cars dump huge amounts of unburned fuel into the cylinders during this process, so an oil and filter change is usually needed immediately afterwards.
As others have suggested, a "forced regen" is the next thing to try. You'll need someone with the proper software. Beware, because a lot of cars dump huge amounts of unburned fuel into the cylinders during this process, so an oil and filter change is usually needed immediately afterwards.