Zafira 09 plate. I have had trouble in the past with the warning light for the pre heat glo plugs.

For some unknown reason it stays on flashing. Eventually it will go off (normally) this time however it has stayed on and there is a smell of burning, and a rattle in the engine compartment. The car was put on the diagnostics at my local garage the last time it happened. And was supposedly been fixed, Here we go again. would appreciate any advice, on this matter, Could ignoring it cause damage.?

Many thanks, Drifter.