Fiesta 1.1 HCS low power/starting problems

[DoTMaTrIx]

First of all every so often either early morning or late night it has a problem starting, it turns over great but wont kick in sometimes it does start but sounds like its gonna stall at any minute pressing on the accelerator does nothing. Also it has lost alot of power can only go up hills in first slow accelerating. I took it to the garage and they replaced the spark plugs and leads they also checked all the fuel lines and filter. Any help would be greatly appriciated

[DoTMaTrIx]

Thanks for all the top advice

[Janesy B]

I take it that it has a carb? That may the root of your issues.