Ask an expert
![craigm1](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
When you turn on the car the engines races up to about 3000 revs, then settles back down after about 2-3 seconds. Does the same when u come to a stop and put the vehicle in park
![Anon](/assets/Uploads/_resampled/ScaleWidthWyI3NSJd/CMSThumbnail-SetWidth75-aa-avatar.png?m=1518003100)
There are a few possibilities. The engine could have an air leak (vacuum leak), a sticky idle speed control valve/ throttle body or a faulty throttle position sensor. A quick scan at a repairer should give an idea of where the fault lies.