Engine shaking a little

Hi,

I've had my Ibiza 130 for about 14 months now and since i've got it I have noticed that on some occasions when I stop at traffic lights the engine seems to shake a little and as a result it feels as the car is shaking. it does it for about 2 seconds and then it stops for about 3-4 seconds and does it again. This cycle carries on.
It only happens when my fott is completely off the gas.
I took it to a garage and the mechanic said that I need to use diesel injector cleaner which I did several times but it didn't fix it.

When I took it to the mechanic, he opened the bonnet and we saw that you can actually see the engine shaking and when I touch the gas pedal a little it stopped shaking.

Any ideas.
Thanks

thanks. any ideas how I can get this software update?

lol ok, thanks

A friend of mine suggested it cold be the engine mount but the mechanic I had seen at the time insisted taht it was the injectors needed cleaning so am not sure but it could be possible.

It happens even with the air-con off. yesterday I took the car to kwik fit to have the air-con re-gassed and they said that I had a leak somewhere so they couldn't re-gas. Anyone know where I could get this problem sorted around the Leicester area?

My knowlegde on how cars work is not that great so have no idea what the compressor clutch is.

An if its the DMF, is that an expensive part to replace?

Thanks for the replies