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Old 10-20-2008, 01:54 PM   #12 (permalink)
cfg83
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1999 Saturn SW2 - '99 Saturn SW2 Wagon
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Metrosexual -

Quote:
Originally Posted by Metrosexual View Post
There are several reasons. Bassically a cold engine requires a richer fuel mixture to run properly until it warms up. A choke on a carburetor used to perform this function, now its done seemlessly through the fuel injection system -you won't even feel this happening. Cold weather requires longer warm up times.
2 Cold air is denser during cold weather your engine can take in a greater mass of air, and add the corrosponding greater mass of fuel. this will give you noticable higher engine perfomance but worse gas milage

3 veriables in the weather, rain, snow, impede performance and increase drag on the vehicle, both aerodynamically and mechanically where the rubber meets the road.
Isn't this the logic behind the CAI (cold air intake)? The goal is to get cool "humid" air into the engine in order to increase the oxygen and thereby increase the amount of fuel injected.

Question: How come some people report better mileage on cold wet days? This sounds like a contradiction to me.

CarloSW2
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