Not the case my friend ....
There is a lot of petrols that do not have egr , loads of Vauxhall models do not have it , many of the new generation Audi’s and bmw petrols do not have egr , Fiats multi air petrol engine do not have egr
The Vw 888 petrol engine does not have external egr control , with new combustion chamber design and individual control of valve lift and adjustable opening and closing of valve timing the engine can dial in late exhaust opening which leaves an amount of burnt gases in the cylinder helping lower burn temps to keep nox down .
Many manufacturers have come away from egr and are using selective catalyst reduction , extra nox cats and add blue systems , this 888 engine also had common rail direct into cylinder injectors ,and injectors in the manifold ..... there is no exhaust manifold , the turbo bolts straight onto the head , it has no water pump .........
I’m going off on a tangent here , back to the plot , looking at the self study literature on the v10 fsi engine it does not have egr so it probably does it’s nox reduction through valve timing control , and like you correctly said,mixing hot gases with relatively cool inlet gases with crankcase mist is a great carbon maker that can add to the Black Death process , in the v10s case just the mixing of pcv in the manifold is sufficient to cause the Black Death and the lack of manifold injectors to ‘ wash ‘ the back of the valves it’s hard to escape from the build up .
On some of the 4 cyl fsi engines they do have egrs ,and a mod you can do (if you have a ecm file writer )is to switch egr off or ‘ calm down ‘ the egr duty cycle to slow back of valve build up .
Anyhow enough of engines ....happy new year everyone 👍
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