Engine Oil. Changing filter only

regens inject extra fuel – some of this especially when the regen aborts/fails finds its way past the piston rings into the sump which dilutes oil.

That’s not a Euro6 issue though.

A taster -although I know your asking to be obtuse and you have a fair handle on the subject.

No, I honestly don’t do that.  EGR has been around since what, Euro 4, and I thought a key benefit of Euro 6 was that less EGR was needed so it should be better for the fuel. I thought BoardinBob meant that AdBluein particular was doing something else bad.

Dpf is still a Euro6 solution as is adblue/SCR but my involvement stops at Euro4 as that’s my D5

 I thought a key benefit of Euro 6 was that less EGR was needed

So I have a 2016 Mazda 2.2 diesel which has not one but two EGR valves. Interestingly the 2017 engines onwards have the adblue system whereas older engines don’t, but the adblue engines have nowhere near the same problems as the older ones, despite them both being Euro 6 engines.

I think the biggest problem with the euro 6 engines is them not being driven in they way they should. They were sold as being cleaner and with super low VED so lots of people snapped them up despite only using them purely for the 2 mile school run and maybe a run to the shops. They’re then shocked when the inlet manifold and EGR valves end up absolutely clogged with carbon deposits.

All that black crap that used to come out the exhausts of diesels has to go somewhere and it’s ending up clogging intakes or finding its way into the oil.

Personally other than encountering the DPF regen issue I had, I don’t suffer the same problems others have with euro 6 engines because I’m doing a couple of 90 mile runs every weekend and 2 x 210 mile runs up and down to Manchester once a month, and very little short run. The engine gets nice and hot and gets a good run rather than barely reaching operating temps a few times a week.

Previously I had a euro 5 diesel engine which in about 50,000 miles I don’t think it ever did a DPF regen and never gave me a single issue, whereas Mazda software in my current car dictates a regen every 200 miles which in turn puts diesel into the oil