2006 Ford Focus 1.6 Petrol - Juddering

[Mattg123]

Hi, 

I am new to this so please bear with me as I am after some assistance of possible please.

I have a 2006 Ford Focus and the car judders under acceleration and is running pretty rough. Just got in from work and was doing it all the way back however just before I returned home, as I stopped at a roundabout, there was a knock sound (just the once) and the Juddering disappeared. 

Coil pack has been replaced, spark plugs look clean, car is well maintained and unsure of the issue. Does anyone have any ideas as to what this could be ? I have booked it into the garage but will be a few days until I can get it looked at. Is there anything I am missing and was the knock relevant to the issues I am experiencing ? Any help would be most appreciated as I have looked on here and seen that it could range from coil packs, spark plugs, leads, throttle body and lost for ideas. 

Thanks in advance

[Russ]

14 minutes ago, Mattg123 said:

Hi, 

I am new to this so please bear with me as I am after some assistance of possible please.

I have a 2006 Ford Focus and the car judders under acceleration and is running pretty rough. Just got in from work and was doing it all the way back however just before I returned home, as I stopped at a roundabout, there was a knock sound (just the once) and the Juddering disappeared. 

Coil pack has been replaced, spark plugs look clean, car is well maintained and unsure of the issue. Does anyone have any ideas as to what this could be ? I have booked it into the garage but will be a few days until I can get it looked at. Is there anything I am missing and was the knock relevant to the issues I am experiencing ? Any help would be most appreciated as I have looked on here and seen that it could range from coil packs, spark plugs, leads, throttle body and lost for ideas. 

Thanks in advance

Did you change the plug leads? If in doubt check them with a meter.

[Micro]

2 hours ago, Russ said:

Did you change the plug leads? If in doubt check them with a meter.

Plug leads may show good continuity, but have insulation breakdown at the high voltages of the coil pack and arc/short to any surrounding metal work.

[Mattg123]

Thanks Russ.

Have had a look at the leads and they seem ok. Do you think this would be the next best option to check ?

[Mattg123]

Apologies, one other thing is that it isn't doing it all the time but getting worse at the moment. 

It just seemed strange with the knock and then it was ok ?