Emission Gases

There seems to be a shortage of understanding here. Please embrace the following:

• CO₂ is one of the two main products of combustion of carbon-based fuels. The other one is water. They both leave the tailpipe of an internal combustion engine as gases. They are dispersed in air as they leave, together with the oxides of other elements present in the incoming fuels, principally sulphur.
• N₂ is present in air anyway to about 78%, so it doesn't need to be removed from the tailpipe gases of a combustion engine. It passes through the engine, having very little chemical effect while in there. There are traces of oxides of nitrogen produced in any combustion process and the level of these depends upon how well the engine and its auxiliary equipment are designed and maintained.
• If one defines pollution as a substance that is in the wrong place, then the only way of reducing it in the context of the tailpipe of a combustion engine that is not in a fixed place is to use less of the fuel substance in the first place.
• "Thinning it" with other gases takes place anyway around the tailpipe and does not reduce the quantities. "Thinning it" in the context of the inlet gases maxes the engine run differently, thereby using more fuel and adding to emissions.
• There are "sweep it under the carpet" solutions for fixed installations' CO₂, one of which is called sequestration. Wikipedia has articles on the topic.
• There are biosphere solutions for all CO₂. One of them is called photosynthesis, which occurs naturally in all green-leaved plant materials. Again, Wikipedia has articles on the topic.

Enough?