Welcome!
At the tune of £170+VAT an injector, I would have tried a lot of other things or waited for your extended warranty to kick in unless someone else is paying for this. If you just bought it, couldn't you go back to where you bought it from or was it a private seller?
I have just been through the same recently myself and unfortunately the latest injectors are not compatible with the old, so you have to buy a set per bank. Luckily the parts manager sold them to me a cost to them, so I saved quite a bit. Changing them myself also helped keep the costs down.
__________________
6MT | COBB PTF | AR DPs | Helix FMIC | Forge DV | Quaife LSD | ER Sports OC | ER CP | AP Racing BBK | Hartge ARBs | M3 suspension | Öhlins Road & Track | HPF Stg 2 clutch | Bastuck exhaust | P3 Gauge
|