Hi all, new to this forum but not new to fords,

Ive got a 1994 fiesta rs1800 which i have had for 2 and half years, was my daily driver for 2 years, never had any probs at all.
It has been stood up in a barn now for 6 months and it was started a couple moths ago and ran fine, however lights were left on and the battery went completely flat.

Wheeled her out today tried to start her (after charging battery) and she wont run properly

It misfires badly (like its running on 3 cylinders), and is undriveable.
It wont start at all when its warm.

I have changed coilpack for known good spare as well as HT leads.
I have tested coolant temp.

Don't think it would be airflow, cos would probably run better then what it is!
Don't think its crank sensor cos probably wouldn't run at all ?
Thinking possibly ECU might of got spiked from start charger?

Really stuck at the mo and need to get the car MOT'ed for friday!
Any help much appreciated,
Cheers,
olly