Help Please - 1.8 Petrol Focus Problem...my First Car And Very Disappointed

[mrsmecca]

Hi,

I've just bought my first car - 1.8 petrol focus 54 plate.

After buying it the speedo stopped working so we changed the speedo sensor which made it worse and some other clocks stopped working properly!
Then we noticed a vac pipe to a charcoal canister wasn't connected so we had it connected but it still wasn't running properly so we've had it on a diagnostics and changed the mass air flow - still made no difference. All the pipes have been checked and now no error codes are showing but it runs like a pile of poo!
I'm so disappointed - paying a car loan and insurance for a car I daren't take my toddler out in as it is so unpredictable.
The garage have checked everything and are now talking about ECU...any thoughts would be appreciated as I really can't afford to keep paying out for checks yet nothing is happening to fix it :(