Oxygenated Gases

[Tom Feller <tomf@mxim.com>]

Winter fuels do have much lower vapor point than non-oxygenated 
gasolines. That is way in most parts of the country the are only sold in 
the winter months. In the warmer summer the vaporation at the pump when 
filling out way the reduce smog from the tail pipes.

CIS injection has always had a problem is vaporation of fuel in the 
injector lines.  Bosch electronic injection have a fuel with the injector 
mounted on short hoses, the fuel is circulated through the rail for the 
tank keeping cool fuel in the line at all times. With CIS the long 
injector lines are dead ended at the injector, so when you shut the car 
off heat for the engine can vaporize the fuel in the lines.  The late air 
shield injectors where designed in part to help cool the injectors.

I find it hard to believe and have never seen a case where oxygenated 
fuel have caused a cold start problem but I am open ideas. On the gas 
milege is quite simple, there is less BTU's per gal. of gasoline than 
per. gal of alcohol. So your milege goes down.


- Tom Feller