I have a Volvo S60 T5 that has already done 398,000km. It still goes like a bomb and sounds great, but has a message that read "engine system service required" and it lately changed to read "reduced engine performance".
There is no obvious evidence of lack of power. Could it have anything to do with ...

Let's hear what your car has on the clock and what advice you can give other owners

Who can give me some advice on 3 issues with my car please?
1. me engine is hunting in idle mode
2. have an error code 042 and would like to know what needs attention
3. my dash screen reeds "engine system service required"

Thanks for your response Sommerfeldt. I have noted your suggestion and appreciated it. What forum would you suggest | take this to?

When I start my (S60) engine it (more often than not) starts hunting - similar to someone tapping on the accelerator. It does not always do it and it seems to be more so under load (when I put in in Drive). I do not notice anything whilst driving, except that sometimes I seem to have less power.
I ...