9 yo Toyota 2.0D, 120k miles. Always professionally serviced to schedule and faultless running until earlier this year.

Back in April we had a fault code P062D come up relating to injectors. Our garage cleared the code (and the car appeared to run OK) and suggested we contact a local injector specialist. He listened to the car but as the codes had cleared (and not come back) he said to wait and see if it recurs.

Same thing happened in June shortly after the alternator was replaced. He said it was probably due to that. The code cleared spontaneously after about 5 days.

August - we get a new code P2002 to do with the DPF which our local garage renewed. Then a week or two later both the injector and DPF codes are back. Our garage sends us back to the injector specialist who, for the first time, actually takes a look. He confirms the injectors are all shot and we agree to get them replaced. At this point the car is in limp mode but it works.

The injectors have been replaced (£1300 for parts alone - which we paid upfront) but the specialist is telling us that the car is now smoking and only running for ~30 seconds at a time before cutting out. There are no fault codes. He's tried removing the exhaust and bypassing the EGR - car smokes at the front but still cuts out. The turbocharger is apparently OK.

My original garage don't want to touch it because they say it must have been something the specialist did. The specialist is claiming that the injector replacement must have uncovered a latent fault, also that he's not a general engine mechanic so can't suggest anything other than we take it to a Toyota dealer - where it could get fixed or quite possibly condemned and either way it's going to be expensive. (He says he's spent ~2 days trying to work out what's gone wrong).

Any advice (practical or legal) as to where to go from here?

With reference to the Consumer Rights Act, can I compel the specialist to arrange to get a professional mechanic to look at it (bear in mind moving it will cost us as it won't drive any more). Or should I cut my losses with him and sort things out myself? Is the burden on him to prove that whatever's making it not run wasn't something introduced by him, or on me to prove that the problem hasn't been building up for a long time and has just been triggered by his work?

Thanks