Hi I have a vaughall insignia 68 plate 1.6 turbo diesel eco Tec and when it's in idle I'm getting a ticking sound from under the exhaust when the engine has warmed up does anybody have any ideas what this could be 

Many thanks Barry 

 

 

 

 

This sounds like the exhaust has a slight leak which is causing the ticking sound on tickover (split has increased in size with temperature increase)

Typically this split could be located in the exhaust manifold or otherwise it could be a joint/gasket located in the exhaust near the front end.

Have someone firmly place a rag over the rear tailpipe and lay down beside the car with the engine running (in a well ventilated area of course) and listen out for a 'hissing' noise and thats where the exhaust gas leak will be located.