Renault scenic 1.9 dci 2004, engine codes

i have a right problem with my car, it drives fine, but on tick over (idle) it shudders the car to bits, so i bought a code reader a Vgate vs600, i can do manual jobs like servicing, ball joints, brakes, you know what i mean, but electrical i am rubbish with, plugged it in and it gave me 2 codes

P0670 & P0380 which both relate to glow plugs and glow plug relay, i put 4 new glow plugs in, and bought a relay and installed that, the codes went off, i was so happy?
the car was still running very slightly rough on tick over, then today i went out and the thing is shaking like mad again, plugged in and the same 2 codes are back?
what the hell is going on, any ideas please?

thanks

Hi mate what make and year and engine size is your car also just check all the vacuum hoses are properly connected and not split

Bodgit and Leggit Garage wrote:Hi mate what make and year and engine size is your car also just check all the vacuum hoses are properly connected and not split

Its a Renault scenic 1.9 dci (2004)
i just hope if its electrical that it has not blown the new glow relay