These are not uncommon combined fault codes on DTi engines. I've done a bit of digging and come up with the following from collected wisdom.
"both of those codes refer indirectly to the pump speed the p1345 is the one that will stop the engine, p1220 will eventually but is more to do with the actual and desired injection quantity, and the pump speed, if you have swapped the pump from another vehicle and the fault is still there i would expect it to be a wireing [sic] fault my hunch would be one of the connectors onto the pump i think you would have to do a drag test on each of the connectors many holes to see if one or more has spread, bit of a bugger but the only way forward i think"
"Maybe, could also have been dirty connects on that electrical connector for the fuel pump!"
"The pump camshaft speed sensor is the small sensor thats attached to the pump control unit via a small ribbon, this sensor detects the pump speed by using a sensor wheel that is attached to the pumps main shaft, if this wheel becomes loose or broken then the pump may need to be replaced BUT the sensor could be faulty and sending a bad signal. Replaced sensor, unsoldered from my edc and replaced with one from a breakers pump edc" - needs a diesel injection specialist to sort out unless you're good with a soldering iron.
"Hi this whole state of affairs, points to lack of fuel, either the injector pump can not suck the fuel through or there is a restriction. You could try a few cheap options first, replace the small valve on the return pipe from the injection pump. The fuel inlet pipe is 17MM the outlet/return pipe is 19mm. keep your vectra above 10L, change the fuel filter top cap for cracks, (you get it separately from the whole unit), check the hose from the fuel filter to injection pumps for air leaks"
"Although most people seem to think that the fuel pump was on the way out and it might well have been, but where the crank sensor went in to the bottom of the engine, the contact where the sensor is was extremely dirty and clogged with oil/greasy black crap. So I think because of how dirty it was down there, the sensor was probably not working correctly and would cut the engine out"
"For anyone else with this code I think I have fixed the problem now. I was on the verge of getting replacement pump and paying to get it fitted but didn't in the end. I didn't want to spend the money on a fault where it might be something as its alot to spend. In the end I think there was a blockage in the sender unit. I read about there being a sort of plastic mesh on the bottom and that gets all blocked up so the fuel pump can't get the fuel quick enough.
Im yet to take mine out but I lifted the seat and disconnected the pipes and blew down them into the tank. One of them took alot of blowing before I could hear bubbles in the tank. So I had a bit of a blockage in the one pipe.
Also the code description is a bit of a giveaway - P1220 injection timing control Insufficent/excessive flow detected"
Only one of these things is remotely expensive, but I still want to know what the mechanic who looked at it actually checked.
Without ruling some things in or out it's a bit difficult to know where to direct you.