Hello
youre right a good 200tdi doesn't need to use glow plugs check the flow/return pipes on top of your tank under the boot floor these little ****s rust and get small pin holes which pull in air causing your symptoms if they are good grease them up so they wont cause hassle down the line it may also be worth checking the cut off solenoid on injector pump they stick especially if you have used veg oil
leekegs