Anyone have any idea of what the average life of 4-cylinder engines is? I realize there are differences between manufacturers, maintenance practices, etc., but does anyone know of any statistical data that shows an average life (in mileage) for the aggregate of 4-cylinder engines?
FWIW, there are also things out of our control that affect the life of an individual engine. Things like local metallurgical defects, tolerances, gasket quality, etc. can shorten the life of an engine that looked great to the manufacturer's QC people before it left the plant. It can go the other way, too, where an individual engine can have fewer than average defects that result in it having a much longer life than average. And then there are events, such as accidents, natural disasters, etc. that can prematurely end the life of an engine.
I keep thinking of my friend's Toyota Camry that had a cylinder wall crack at about 140K miles. A lot of people I knew with Camrys had them go well over 200K and get close to 300K. His was an example that didn't make it as far as the average for that vehicle (although people who lived 30 years ago would have been glad to have an engine that made it to 140K!).
My in-laws got well over 200K on an '88 Camry (which they passed on to my brother-in-law, who eventually sold it) and now have over 200K on our old '91 Honda Accord. Both are 4-bangers.
All we BITOGer's can do is give our engines and vehicles the best available TLC in terms of motor oil, antifreeze and other fluids (along with other maintenance) we can to keep our rides on the road as long as possible!