2003 Vauxhall Vectra coil pack

Coil packs are very common and if no3 cyl is misfiring it would give erratic idle and poor performance . If it's knacked , you are only on 75% power or a cyl .down .If the engine has been running rough and showing code , no reason to doubt garage findings .

took it to garage today it was not the coil pack its not the cylinder, they said its to do with the injectors which they sorted it then flew through the mot,two miles away from the garage the eml came back on.
the revs have calmed down also runs better but seems to kangaroo in 2nd gear any ideas

back again this morning different code reading looks like its the mafm going to swop it over monday to see

My vectra (s reg 1.8 petrol) Also just failed an mot on emmissions.
Misfire on idle but runs fine. no engine fault light. Checked hoses spayed carb cleaner into carb. Did paper clip test on engine management. showed about four usual faults i.e. airflow sehsor MAF unit
o2 sensor and coolant sensor but these could be old ones. I'm told if I disconnect the battery for about 4hrs codes will go? currently doing this. I read that on the 1.8i it could be the earth wire on the sensors to the ecu and gave a field fix 2003 but on my vectra the wires are different colours. Also need a diagram to show where the sensors ecu are on the engine.
Any ideas anyone!

Thanks