# Rough Idle \_ Mazda Protoge

**URL:** <https://community.cartalk.com/t/rough-idle---mazda-protoge/24212>\
**Category:** Maintenance/Repairs\
**Created:** [January 2, 2009, 3:38am UTC](https://community.cartalk.com/t/rough-idle---mazda-protoge/24212 "2009-01-02T03:38:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jackgl](https://avatars.discourse-cdn.com/v4/letter/j/ec9cab/32.png) [@jackgl](https://community.cartalk.com/u/jackgl)\
**Post date:** [January 2, 2009, 3:38am UTC](https://community.cartalk.com/t/rough-idle---mazda-protoge/24212/1 "2009-01-02T03:38:55Z")

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2003 Mazda Protoge starts and runs good, with exception of idle at red lights, etc. Idle gets very rough to near stalling. I changed plugs and air filter. Any suggestions?

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<div class="post-metadata">

**Author:** ![Manolito](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/manolito/32/3070_2.png) [@Manolito](https://community.cartalk.com/u/Manolito)\
**Post date:** [January 2, 2009, 5:39am UTC](https://community.cartalk.com/t/rough-idle---mazda-protoge/24212/2 "2009-01-02T05:39:22Z")

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Rough idle with a warm engine is generally the result of a vacuum leak.

Could be a vacuum hose split or disconnected, a failed intake manifold gasket, a leaking EGR valve.

There are other possible causes besids vacuum leaks, and other sources of vacuum leaks, but that is where I would start looking.