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Q: Ignition takes longer and idle goes higher after ignition

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  1. Sometimes, not always, when I hit StartEngine button, it would take about 2~3 sec. to start (normally it is instant-start).
  2. After the ignition though, it happened only once, the idle went up to 1500 rpm, which it normally is around 700~800 rpm. I was stoned for about 4 sec. and I then shifted from P to D, and the idle went back to normal right after I shifted the gear. I live in San Diego, and it is not like freezing cold even in Winter. At night the lowest temperature is around 44.6 F.

My car has 17800 miles.
My car has an automatic transmission.

This may be a sign of a vacuum leak. High idle speeds or in some cases rough idle, stalling and hissing sounds are common signs of a vacuum leak. When a vacuum leak is present in an engine, this causes an excessive imbalance in the air/fuel ratio which creates a loss of power and causes the motor to run at a much higher RPM as a result of the increased oxygen present in the fuel charge being injected into the motor. The excess air present in the system while starting may also cause the slight delay in starting as the system struggles to find the correct air/fuel balance. I would recommend having an expert from YourMechanic come to your location to diagnose your vacuum leak as these can be very difficult and time consuming to trace.

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