I posted this on another forum and had some great advice which I'll edit and write below my initial comment. Just wanted as much advice as possible so thought I would try my luck here too
"Ok, So I'm guessing I'm in for an expensive fix but wanted a few opinions before I bite the bullet.
I have a facelift 53 plate 156 2.0 JTS
Has a bad misfire on cylinder one. The injectors and coilpacks have been swapped over to see if the fault stays at cylinder 1 and it does. Ergo the injectors and coilpacks are fine?? (he says, not really knowing if this is fact!)...
Wires seem to be ok and a mechanic feels it's the ECU which may need remapping. He's not an Alfa specialist and I am aware of the annoying injector issues so fear those expensive buggers may be to blame. I'm going to take it to my local specialist who are good guys but they say first point of call is sending off the injectors for checking....
I guess I'm hoping that some miracle man can point me to another potential cause which I can check before I go down the expense route. Any views on potential ECU fault?
The general consensus and advice I have received to the above post so far, is that my mechanic was less than competent and a remap is probably not the wisest course. I've also been asked if he erased the codes and reset the ecu between tests.... I would like to think so but based on other "advice" from him, maybe not! I'm looking to invest in some diagnostic software myself to do the tests, so my first question is what to buy and where?.
I have been advised to check sparks and sparkplug wells and also wiring (which seem ok)
The MSCF light is on and flashes and beeps at me, which I have been informed is a cat damage warning and could be the coil packs?
A compression test has been done and all cylinders seem fine?
Any further thoughts gratefully appreciated!