I have a 99 cabrio gl manual 5speed transmission and the idle is bad it stays around 1rpm but goes a little above and a little below when I am at a stop like a red light stop sign ect. it shakes when its in idle I changed the plugs but they looked fairly new but they were ngk not bosch I replaced them with ngk plugs again forgetting they recommend bosch. could that be the problem them simply not being bosch plugs? I do most of my car work myself because I am a single mother of 2 young children and labor is simply to expensive for me. this started a few weeks ago and does this everytime I drive it. sometimes after its warmed up from driving a while the idle is ok but then it starts again within the same drive to my destinations. it has misfired a few times not many but the idle is an everyday thing.