We used to test automatic choke coils and heat risers with a blast from a CO2 fire extinguisher. That -90 degree F. boost made them react in a hurry, no matter what the outside temperature or under hood temp might be.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!