I have a 2007 Mercury Mariner. Is it normal when the car idles at 2000 RPM for about 4-5 seconds if it is cold when I start it? I drove the new car for two months in warm temperatures and then it spent two months in a body shop after a major front end accident. When the car was returned to me it had become cold in Ohio and I noticed the RPM seemed high to me. The dealership says it is normal. Does anyone else have a similar cold start in a Mariner?
One of the primary inputs into the engine management system during a cold start is the engine coolant temp sensor. If the coolant temp sensor reaches a certain low temperature, the engine management system goes to a default engine RPM when the engine is started cold. Once the engine is running for those few seconds, the computer adjusts the engine RPM’s dependent on the signal it recieves from the coolant temp sensor.
So, it’s normal.