OK the other halfs td4 would not start, narrowed it down to the regulator on back of high pressure injection pump. Changed seals and started fine ran OK but now when car is up to temp it goes into limp home mode and eml is on. Error code is "4496 rail pressure monitoring deviation" Could the regulator be faulty or worn? It has had a new delivery pump and filter? Also swapped rail pressure regulator as had one lying around but same code, Any help appreciated.
