# Engine running fast

**URL:** <https://community.cartalk.com/t/engine-running-fast/10368>\
**Category:** Maintenance/Repairs\
**Created:** [February 8, 2008, 8:28pm UTC](https://community.cartalk.com/t/engine-running-fast/10368 "2008-02-08T20:28:24Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![agrevbuzz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@agrevbuzz](https://community.cartalk.com/u/agrevbuzz)\
**Post date:** [February 8, 2008, 8:28pm UTC](https://community.cartalk.com/t/engine-running-fast/10368/1 "2008-02-08T20:28:24Z")

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I have a 1990 ford probe with a v6. It sounds like the engine is running fast. The Tachometer looks normal, What could be causing the sound?

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [February 8, 2008, 10:26pm UTC](https://community.cartalk.com/t/engine-running-fast/10368/2 "2008-02-08T22:26:28Z")

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You may be mistaking the engine cooling fan sound with the engine sound. Open the hood and see if the engine cooling fans are running constantly . If they are, the radiator may be low on anti-freeze, or, there may be another problem.  
Contrariwise, the tachometer may be wrong, and your ears right. Have a mechanic check it out.

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**Author:** ![MikeInNH](https://avatars.discourse-cdn.com/v4/letter/m/a587f6/32.png) [@MikeInNH](https://community.cartalk.com/u/MikeInNH)\
**Post date:** [February 8, 2008, 10:41pm UTC](https://community.cartalk.com/t/engine-running-fast/10368/3 "2008-02-08T22:41:17Z")

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I had the same problem with my first pathfinder (90). The clutch on the clutch-fan went. I replaced it and engine sounded normal again.

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**Author:** ![americar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/americar/32/42_2.png) [@americar](https://community.cartalk.com/u/americar)\
**Post date:** [February 8, 2008, 10:48pm UTC](https://community.cartalk.com/t/engine-running-fast/10368/4 "2008-02-08T22:48:37Z")

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“The Tachometer looks normal”  
What is the tachometer reading at the time the engine sounds like its running fast?

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**Author:** ![agrevbuzz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@agrevbuzz](https://community.cartalk.com/u/agrevbuzz)\
**Post date:** [February 11, 2008, 1:58am UTC](https://community.cartalk.com/t/engine-running-fast/10368/5 "2008-02-11T01:58:38Z")

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took me a while to get back. The Tach is reading about 2000 rpm when it sounds like its running fast. This is about normal for 55 to 60 miles an hour in 5th gear.

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [February 11, 2008, 3:17am UTC](https://community.cartalk.com/t/engine-running-fast/10368/6 "2008-02-11T03:17:54Z")

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And IS the car running at 55 to 60 mph, in 5th gear, at 2,000 rpm?

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**Author:** ![agrevbuzz](https://avatars.discourse-cdn.com/v4/letter/a/8dc957/32.png) [@agrevbuzz](https://community.cartalk.com/u/agrevbuzz)\
**Post date:** [February 11, 2008, 4:44am UTC](https://community.cartalk.com/t/engine-running-fast/10368/7 "2008-02-11T04:44:50Z")

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I assume so. This is my wife’s car, and she is the one complaining of the noise. I have tried to duplicate the conditions, but have been unsuccessful. She says that she is going the normal speed (55 to 60) on the highway (she commutes 45 miles to work) and the tach is in its usual position around 2000 rpm.

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [February 11, 2008, 5:00am UTC](https://community.cartalk.com/t/engine-running-fast/10368/8 "2008-02-11T05:00:28Z")

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She may be hearing the radiator fan running. The air flow, from the forward motion of the car, should be enough to cool the engine at 50 mph. Check the antifreeze level in the radiator. If the engine is running the correct temperature at 50 mph, and the radiator fan is running, the radiator fan switch may be stuck closed, or the fan relay may be stuck closed. As radiator fan control circuits go, this one isn’t complicated.
