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Q: Racing engine

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on occasions when slowing down to stop just as I come to a complete stop the engine races

My car has 80000 miles.
My car has an automatic transmission.

The idle may be high due to a vacuum leak at the pcv hose where it connects to the back of the intake manifold. It gets a hole in it causing a large vacuum leak. The hole may change in size depending on engine heat. Check the hose to see if it is soft at the intake port connection. If it is not bad then you may have a sticking idle control valve. Check for IAC computer codes and replace if needed.

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