Try page 250-2 of the Bentleys 240 manual. This book states clearly the purpose of the preheat: driveabilty, economy and emissions while cold. It is common knowledge amongst Bricksters that the preheat has no noticeable effect on driveabilty or economy and hence it is usually diabled to avoid mass air flow sensor cooking. I repeat yet again, it has no effect on starting a cold engine.

The preheat system has a very marginal effect on emissions and emissions have never been shown to have an effect on your global warming and we now know that global warming was a myth. So, best to just disable the darn thing.

The Bosche manual I refer to is by Probst and the title from my memory is Bosche Fuel injection and Engine Management. I do not have it with me so I cannot quote from it. This book explains in great detail how the ideal mixture is obtained by the different systems. You should know that too much O2 (lean) is bad for emissions too so please do not go by what El Rushbo says.

Insults do not really affect me so I guess I did not recognize your attempts to offend.