I have a few problems with my ford focus,

1. Over the last few months my car tends to shudder like it is going to stall or cut out when driving, it happens randomly without any warning, usually its when just driving between 20-30 along a road, then all of a sudden it just shudders for a few seconds, then it ok again for a while. the only thing i notice is it seems slightly rough before and after it happens,

2. the last 3-4 weeks now the cold weather is coming in, when i drive away from starting the car cold it tends to stutter slightly when changing up into 2rd gear and applying the acelorator.

3. the car started lastweek as normal for about 10-15 seconds then it cut out, i tried to start it again but it was cranking but not turning over, i tried it several more times over a few hours but it wouldnt turn over the engine, just kept cranking but wouldnt turn over. called the AA, he tried several times to start it and after about 40 mins he finally got it going, he said he didnt know what the problem was and to book it into the garage to get it checked

ive had to the car in the garage several times but they say there is no fault that they can see, ive tried to take it into the garage whilst its happening but when the machanic comes for a drive the problems has sorted itsself again, its now costing £70 everytime they look at it and its mounting up so hoping someone can help

there is no warning lights on the dash during any of these problem.
I hope someone can help me as its getting worrying now driving a car that the garage dont know whats wrong with it.
Thanks.