skoda fabia juddering in idle after about 1 minute

hello every one and thanks in advance for taking the time to read this.

basically it started at a supermarket everything was absolutely fine but pilled in to a parking space as the engine light came on flashing so I turn it off and went in and was gone for about 10-15 minutes and turned the car on and the engine light came on again but it was solid yellow so I revved it up a bit about 3500 rpm and held it for couple of seconds and let it go back down. as it did it felt extremely juddery and it started flashing agagin.

so I turned it off for a few minutes and turned it back on and left it to tick over in idle ( engine warning light onagain) after 30 seconds idle became very juddery again.

try to limp it home as I was about to pull off it wouldn't rev past 2000 rpm and be juddery below 1000 rpm.

I pulled into a staff car park bit turned it off again and a guy came and helped me and as he was revving high it sounded like a tiss-tiss-tiss sound in the engine area and couldn't locate it. anyway he said it seems fine to drive home so I did not letting it drop below 1000 and changing before 2000. has anyone got any idea what this could be?

thanks again