I hope you don't mind me posting here - I have a Zafira - but the problems relate to the CDTI 150 engine which is shared with the Vectra so I wanted to tap the expertise on here
Car is a 2007 Zafira with CDTI 150 (Z19DTH) engine, 54k miles.
Bit of recent history leading up to current state:
2 or 3 weeks ago, the water pump siezed and shredded the cambelt
Local (independent) garage found a number of broken rocker arms, and replaced them (they actually replaced all 16 as a precaution). New water pump & cambelt kit, and serviced at the same time.
Car drove OK to start with, although I felt it was a little down on power (however I don't drive it regularly so wasn't 100% sure).
After about 20 miles, warning light came on, limp mode. Pedal test showed fault code P242F (DPF sensor range, I believe). Fault went away after restarts and car seemed to drive fine again, but always came back a few minutes later. Car was also displaying 2 other faults related to camshaft position - which I suspected were old ones from when the cambelt went.
Got someone local to clear the codes and went for a drive to see which ones came back. A few miles later, warning light back on, back into limp mode. Only fault showing now was now P2279 (Air intake leak, usually means EGR I believe). Car became so low on power that I could barely move from a standstill and was dangerous to drive, so I parked up and called AA.
AA found the P2279 code, decided it was the usual EGR problem (second one he'd done that day...) and fabricated a blanking plate from a drinks can.
Car started, code gone. Recommenced journey.
Few miles later - warning light on again, this time the P242F (DPF) code.
Managed to finish journey with a combination of rolling restarts every few minutes.
Took the car out several times over the weekend on fast runs to try and get a regen going. But kept going into limp mode after a few minutes.
Gave up and headed home. Got out of car - heard the familiar tinkling & smell of a hot exhaust, looked underneath - DPF glowing red so at last a regen had commenced, jumped straight back in and went for a 30 mile fast drive. Warning light stayed on from startup for a few minutes then went off.
Car felt much better after the regen, and no warning lights.
Thought that was the end of it, but...
Next day driving to work, covered 20 miles OK, suddenly very loud tapping from the engine, loss of power, noticed a brief puff of smoke out the back, warning light came on, so I pulled into a layby. Engine was still running, but roughly. AA towed me back to the garage (after I explained the symptoms he didn't want to risk trying to start it).
Garage found 3 of the exhaust rockers had broken. Why ? We have no idea. If it had just been a single break, I'd have suspected a manufacturing defect, but for 3 to go at once, on 2 out of 4 cylinders ?
I think two were cyl 4 and one was cyl 2 (not 100% sure).
They've double-checked cam timing and say it looks spot on.
Anyway, rockers now replaced, engine reassembled.
Engine starts & runs, but roughly - like it's only firing on 3 cylinders. Sounds OK though - no ominous noises.
Pulling injector cable off injector #1 results in no difference, pulling #2, #3 or #4 results in it running rougher. So it's related to cylinder 1 or injector 1.
Garage had some fancy little test lights that plug into injector connectors and flash when injector signal received - plugged it into injector 1 connector and it flashed away merrily, so it looks like electrical signal is getting through to the injector OK.
I suggested the copper injector washers - but they said they'd fitted new ones.
Garage are currently waiting for someone to come and do a spill/leak test on the injectors, to show if one of the injectors is the culprit. I guess the results of that will dictate what happens next.
In the meantime, I wondered if anyone has any thoughts on what might have gone on to cause the 3 rockers to break, and why the engine is running rough ?
Thanks for any input !