As temp sensors go bad, the resistance tends to drift upwards, which is indicative of a "colder" temperature.

If this is what's happening (likely), the computer thinks that the car is getting more air intake than it is, since cold air is denser than warm air.

If the computer thinks that it's getting nice thick cold air, it will increase the amount of fuel delivered to keep the mixture correct. But, if it's just a faulty reading then you wind up with a rich condition.


-tp