odd idle charateristics

[24HRS]

Guys , i have a 2006 peugeot parnter 1.9 with the dw8 engine

my alternator died before xmas

replaced it with another - the engine sounded funny - diesel knocky kinda way

noticed idle was about 900 rpm as oppose to 800 before new alternator - then when warmed up it was 1100 rpm. - ive checked the stop position and the cable tension (when cold and warm) on top of the IP already

I noticed there was no buzz sound when i turned ignition to heaterplug position - i believe thats the advance solenoid so the engine has gone to max retard or advance which would account for the hammering i get at low rpm. but starts on the button first turn no bother after heating - and is a bitch to start if you dont use the plugs so the plugs are working fine

where is the relay for this located so i can test it - diagrams for this engine are like hens teeth !

and if its connected in anyway the backlights for my dash radio display unit never worked after the alternator was replaced even with a new fuse ( i realise on a modern car is likely isnt but the sequence in what circuits are wired up like in my 86 landy says anything is possible ........ )

thanks