TheMK wrote:after changing the fuel type (lower octane, but also from a different supplier), the problem went away.
I went the other way and have been running 94 octane ethanol free petrol.
I have several small generators and have used this method for years. It seems that the ethanol blend gums up the fuel system at least on these little engines. I believe this occurs when the fuel sits in the system for a while.
Starting the Rex more often can keep the fuel moving and prevent buildup. I am sure that there are additives that can help as well but BMW would have to be okay with using an additive if there is a warranty to maintain. I run my Rex every other day for 20 min intervals to keep the fuel moving.
This is just my take on possibly preventing fuel system issues. I am interested to hear what others are doing to keep the Rex running smoothly.