Mechanic says they repaired a too-high-idle-rpm by cleaning “choke”. Sure enough, problem solved. However customer gets to thinking, this couldn’t possibly be true, the car is fuel injected, so it has no choke. “Solution” is that some fuel injected Fords at first used a thermostat gadget to open the throttle a little so to bump the rpm during cold weather. Seems to me the Car Talk brothers are using the word “choke” pretty loosely … lol … A “choke” imho is used to increase the fuel/air mixture. Increasing the throttle opening doesn’t change the mixture. Carbs often combined the choke mixture function with an increase rpm by slightly cocking open the throttle, so maybe that is what they mean?
My late-70’s VW Rabbit was one of the first widely sold cars w/fuel injection. It used a gadget called the “auxiliary air valve” which opened a little rotating door (by thermostatic coil-spring action) & allowed extra air into the intake manifold when the ambient air temperature was cold. Is that the method early-era fuel-injected Fords used too?
