Hi all... ok when I started my e220 cdi this morning it was like it was running on only 3 cylinders.... the idle hunts a bit too, but it's always done that. when held at 1500rpm it ran on all 4... any idea what this could be? it runs fine when hot. I thought maybe a glowplug was down but shouldn't that re-light the glowplug light on the dash? is there an easy way I can check my glowplugs?