Volvo Repair: 2001 xc70 2.4t, cam code, cat converter

Question
hello, I drive this car over 100k and enjoy it very much,except when the emission service light is on, it happens when there is a traffic jam or slow traffic,my dealer looked at it several times replaced o2 sensor(doesn't help)the engine makes more noise and has less power also fuel consumption increase also idle running is fluctuating.when the light goes of everything seems to be normal.i have read out computer it says :
-cam adjustment failure
-irregular running on cil 3-5
it would be great if you can help me solve this problem.while it seems my dealer cant handle it!?

Answer
Dennis, on these cars its usually the Cat converter that is going bad.  They probably dont want to share the code with you but I would be that it says 3 way catylitic converter, effiency.  If the cam code is on, it may be the valve, or someone didnt install the cams correctly if the took them off to do an oil leak or something.  Roger