Hi every one. I have a silly question that has been on my mind ever since I got my smart. When the outside temp is above freezing an electric motor comes on in the engine compartment, runs for about 30 seconds. Then I hear a relay in the dash go click and motor stops. It only does this during a cold start. After the recent software upgrade it now increases it's RPM just before shutting off. Now, I'm just curious. What is it doing? Fuel pump? Oil pump? Thanks.

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It is probably the secondary air injection pump to help get the catalytic converter up to temperature. Our Cadillac has one but it is more subdued noise wise.

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