Hi guys its been a while since I have posted. any way I am now at the end of my tether, I have a 2003 stilo now and its coming up engine fault.... as you can imagine beep beep and a error on my screen.

plugged in using my bosch kts 650 and fault code showing Is a camshaft fault.

apparently this happens after the cam belt has been changed...
I changed mine 4 weeks ago and has only just come on.

it basically only appeared after I fitted a centre exhaust and after cat lambda sensor

can one shed some light before I throw more money at it ??