shuddering whilst driving on mk3

[bluemippy]

Hello every body I own a mk3 focus st and driving home from work the other night whilst doing around 30 mph in 4 gear and then did slight acceleration the car started to act funny it was either misfiring or the car was shuddering, if I floored it it pulled no problem slowed right down dropped it in to fourth gear and accelerated and it played up again only last till car picks up a little more speed but does it in other gears as well. Went to my local garage they took out the plugs and said that could be the problem so they changed them but the car is still the same,Now they are stumped as they have never seen this before. The car is out of warranty, has any body got any ideas? Any advice or help would be very grateful.

 

 

[alexp999]

When you say garage was it a Ford dealer?

PCM update could fix it or possibly TSB on engine wiring.

[bluemippy]

The garage is a local  ( non-ford) with out sounding stupid what is a pcm update or tsb? Thanks for any replies.

[alexp999]

PCM is basically they module which controls the engine. Often an update of the software running on the module can fix issues like this.

 

TSB is basically a set of works to be carried out for known issues.

[bluemippy]

Many thanks for the replies I will speak to the garage in the morning and see what they say