Glow plug relay light often doesn't show resulting in a bad engine start, why ?

[Fastlife91]

In December I noticed the glow plug relay light wasn't showing on the dash, when it rarely would it was very briefly, likes 1 or 2 seconds  but the car still started and drove fine.

Over these last few weeks when I start the car from being parked overnight  AND WHEN THE GLOW PLUG RELAY LIGHT ''DOES NOT SHOW ON DASH''  it starts very weakly and then idles awfully with pale blue smoke out the exhaust for a minute or so feeling like the car wants to stall and it sounds very loud and rough for about a minute

 

BUT

 

On the rare occasion I start it from being parked over night and the glow plug relay does come on briefly ( for like 2 or 3 seconds ) it starts right up, no smoke or nothing, and perfect idling

 

 

Is this likely due to the faulty glow plug relay ( didn't have any trouble with it in the winter though unless it wasn't too bad then )

 

thanks