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Remove the whole box and blow it out with air. If you have air tools it comes out very quickly and its much smarter to do it this way so you can check your tac, (thermostatically controlled air cleaner). It should be open to cold air only so you don't kill your AMM, (air mass meter). They get stuck in the hot air or exhaust position and that kills the AMM. You can remove the sensor and take the silver push rod out. Replace it with a longer nail so it won't move and will only keep the flap open to cold air. This is something that every new Volvo owner should check when they get a new 240 or if they get a new girl friend that owns one. Some people like to just replace the sensor if they live in very cold weather to prevent throttle plate icing.