Uneven tickover

[Petlew]

My 2005 2.0 litre T Spirit has just come back from a full service. And, has developed a slightly uneven tick-over, with any of the doors open, a vibration can be felt touching the door edges. Under the bonnet the motor can be seen moving slightly on its mountings.

It has to be said, this unevenness is not excessive, but can be felt throughout the car (if you know its there and feeling for it). Any slight increase of engine revs largely cures the problem.

However, the rev-counter seems to read the correct tick-over speed when the engine is at normal running temperature, but the uneven tick-over is still there.

In truth, I'm not 100% sure this has not been noticed before the service (so I'm loath to blame my usually excellent independent garage), but it usually goes off after a short distance travelled, but is not now.

Any ideas?

[Petlew]

As an additional piece of information. I also have a 52 plate Avensis 1.8 litre that recently developed a serious misfire. This was fairly easily fixed with one new spark-plug pencil-coil which had broken down entirely (which I did myself). That engine is now running like the proverbial sewing-machine.

I wonder if one or more coils is giving trouble with the 2005 engine.

Do pencil-coils become slightly faulty, or, do they either just work or not work with nothing in between?