One is for sure sometimes they cough, maybe some odd form of bacteria. Was for some time related to a certain brand
the other kind
got diarrhoea, the hot section ended up on the runway or was spread over some area. Now clear to me it was infection.
We better leave germs and other organic stuff in the fuel where it belongs.
For sure is just margins (in all areas) are getting closer, when in doubt switch on the ignition as we learned the old days when engines were less reliable and we had to expect in ice and turbulance a sudden stop without.