Back in the sixties there was a man who developed a "pill" that you dropped in your tank with water, and then a battery charge broke it into hydrogen and oxygen, and the engine ran on this, giving back a charge to the batteries while you drive around.

You only needed oil for lubrication. But apparently the oil companies bought the complete rights to it through a third party that wasn't supposed to be connected to them, and hid the details from the public.

And how many revolutionary engine designs are removed from the public eye after mysterious "investors" get in charge of research projects, usually their traced to car and oil companies, if traceable at all.

Car companies have too much invested in wasteful designs and are partly owned by oil companies in many cases, and oil companies want sales and profits without costs.