Car: 05 Mustang V6 5 spd.

When I start the car and drive for a few minutes, put it in neutral and coast (touching no pedals), the engine will rev itself up to around 2,000 RPM's. When I push in the clutch the RPM's will drop, and when I come to a complete stop the RPM's will drop back down to around 1,000 which is normal. At times the RPM's will shoot up and down from 1,200 to 2,300 RPM's. Not only is this wasting my gas, it is obnoxious coasting to a light and having my car revving itself. Any ideas on what could be causing this? It has been happening since I bought the car about 6 months ago, but has progressively getting worse and more frequent.

Thanks for reading,
Zach Manolio

 

take it to the dealer an make it there problem. It should still be under warranty.

 

At idle, even if you're idling at a few thousand RPM, there isn't any load on the engine, and you're really not consuming much gas. Don't even worry about that aspect of it. This is a very small percentage of the fuel consumed with any load on it, like when the car is moving.
But yes, take it to the dealer..

 

Umm Warranty?

 

Throttle Positioning Sensor? (TPS)

 

or mass airflow sensor or 02 sensor..but then again you should be getting a engine light...