Exhaust gases does not work as it is CO2, If it is CO then It would help but that's highly unlikely, the traces for CO would be to small in most cases. It proves no better than using ambient air. Ambient air contains 78% Nitrogen and Nitrogen isn't flammable CO is flammable and CO2 Is not. Ambient air also tends to Absorb Oxygen to the best of my understandings which prevents higher volatile behavior, its a volitile reducer! I believe that the Ambeint air Attataches itself to the Hydrogen element and the Oxygen element also somehow becomes absorbed in the CO2 and Nitrogen in the air. Stan stated Clearly that he used (Added) Nitrogen (and other non combustibles) which I believe to be Ambeint air, to the hydroxy. Well, 78% of the air be breath is Nitrogen so no lie there.
You have to understand, You have a Pure Oxygen and A Pure Hydrogen Element produced, it is Ready to Bond with whatever will accept it or whatever wants to share or take an electron. When you start adding carbon to an Element something is going to happen, Its chemistry its suppose to.
Our key here is to produce a Synthetic gas, It may or it may not be a new gas, We do not understand it yet!