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Q: Idiling issue

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As the car begins to slow down the car idles high to about 1500-2000 rpms and goes down after coming to a complete stop. I also have to apply more force than normal on the brake to slow down. This occurs most of the time. What's the problem?

My car has 50000 miles.
My car has an automatic transmission.

The power braking system in your 2012 Toyota Highlander uses an engine vacuum to increase the operators brake pedal effort and applies a higher amount of pressure on the brake assemblies. This function is found in today’s higher performing vehicles.

A high idle can be caused by a vacuum leak causing the engine to increase it’s RPMs and add fuel to compensate for the added air. Have a technician inspect the performance readings with a scanner as the vehicle is running. As a safety precaution I’d recommend having the braking hydraulic system inspected for any failures as well.

If you decide to get this fixed, consider YourMechanic, as a certified technician can diagnose your high idle and braking symptoms firsthand. From there you’ll have a clear idea of what needs to be fixed.

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