Low idle, nearly cutting out

[DomP182]

Right so having sorted a bad earth causing the immobiliser to not allow my 172 to start I've now got a new issue which is a low unstable idle which is close cutting out.
On closer inspection I can hear the coil making irregular clicks like an arching sound, is this likely the problem?

Loosing the will to carry on....

 

[flebay]

On closer inspection I can hear the coil making irregular clicks like an arching sound, is this likely the problem?

More likely to be the ht leads should be able to see it in dark when you spray them with water.

 

[DomP182]

One for later then, should I just mist them with a spray bottle? It certainly sounds like arching to me

 

[DomP182]

@flebay Its arching from no.3 coil post but only intermittently, is this a lead or coil problem or both?

 

[R3k1355]

Start with the leads

 

[flebay]

@flebay Its arching from no.3 coil post but only intermittently, is this a lead or coil problem or both?

If you remove number 3 from the coil and there is no cracking to the plastic of the coil (white part if its genuine) then you can be sure its the leads.

 

[DomP182]

I've noticed the resin that infill the coil pack has shrunk away from the terminals, one is even a bit loose

 

[flebay]

I've noticed the resin that infill the coil pack has shrunk away from the terminals, one is even a bit loose

Thats not normal, guessing it not a genuine coil pack, you usually get a fault on 2 cylinders when the coil goes because of the way they fire.