Ford Ka misfire

[amjenn]

My wifes Ford Ka, 2003 with Duratec engine, has a misfire at low RPM under load. I have so far replaced Plugs. HT leads and coil. At low revs in 2nd or 3rd gear, small throttle opening, no misfire. If I increase the throttle the engine misfires once or twice and then picks up. Any advice on a possible cure would be appreciated. I asked Ford to look at this when it was in for service recently but they did not report any problem when connected to their diagnostics.

[mafioso]

I had exactly the same on mine. Same age and engine. According to dealer it was HT lead number 3 and replaced it. Since then it has been fine but replaced the plugs with NGKs (the ones they put in the SportKa) and it's made the throttle that little bit more responsive! You say you've replaced all plugs and leads, but are they still Motorcraft ones? If so, get some proper ones, as Motorcraft are crap!