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Old 1st December 2008, 02:27   #1
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Default Speedo Reading/RPM Issue.

I went on a 300 Km drive today morning in the Accent.

Before leaving in the morning I drove the car for 3kms in the city to fetch groceries.

Left at around 8Am and after 5kms and refuelling,I was on the Highway.
The Car's temperature Needle was showing normal temperature in the marked zone.

Soon the speedo readings were in three digit terittory.

I Was doing 100 on speedo,a glance at the RPM and got a tiny scare.
It was showing 3K RPM at 100 than the normal 2.7K.

I stopped and started,again it was nudging 3K at 100.
Now my mind inclined towards a weak clutch,but what the heck,it was working perfectly and I Hardly ride the clutch or drive in heavy traffic,and the car has 39K on ODO.

Normally it does around 115@3K RPM in 5th gear.

As I covered Kms I could notice that after 30Kms I was doin 100@2.9K RPM and things settled down to normal as I reached my destination 110kms away at around 10AM.

All Readings were normal while coming back.
and again same higher RPMs were noted late in the evening after the car was parked for a few hours.

What causes this?
Clutch?
ECU?
Something else?
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Old 1st December 2008, 06:40   #2
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My suspicion is around the clutch only. Of late I have seen clutch giving in on cars within 30-35K on odo. Recently there have been few cases on t-bhp also.

Understand that you do not drive in heavy traffic much. But does your normal driving include lot of short drives? If so that can also lead to early clutch wear.

My suggestion is to keep a watch on the clutch. If such a thing occurs again, then get it checked. Also keep a tab on FE. Slow and minor deterioration may not be noticeable in everyday driving but the FE will start dropping by 5-10%
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Old 1st December 2008, 07:28   #3
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I had thought of a weak clutch at first,but this happens only when temp out side is low that is in the morning and late evenings.
Car is running perfectly otherwise.
this has made me think
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Old 1st December 2008, 07:47   #4
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Interesting that an accent should go through this!
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Old 1st December 2008, 14:58   #5
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Strange indeed.

Quote:
Originally Posted by akshay4587 View Post
What causes this?
Shooting in the dark :

Incline?
Wind direction?
Alternator not getting the right voltage when cold?
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Old 1st December 2008, 19:41   #6
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Quote:
Originally Posted by GTO View Post
Strange indeed.



Shooting in the dark :

Incline?
Wind direction?
Alternator not getting the right voltage when cold?
I dont think Incline or wind direction can cause this.
car will hit NH 22 tommorow afternoon lets see how it fares.
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Old 1st December 2008, 19:47   #7
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Could it be the AC? Was your AC on?

A normal AC will increase the idling rpm by about 500 revs. If it is not working properly, it might increase it further. Not sure if this affects running rpm too.

EDIT: Re-read your post. Your car is going slower at the same rpm when the ambient temperature is cooler, i.e. early morning and late evenings. I'm wondering how can cold(er) air reduce the power being produced at a fixed rpm? Could it be that sensing more dense air, the ECU is letting in more fuel and running rich at the same rpms? In that case the accelaration should improve as well. Akshay, did you feel a difference in performance?

Last edited by DueLLeR : 1st December 2008 at 19:57.
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Old 23rd November 2009, 10:56   #8
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Winters are here and so is this issue
Clutch has been ruled out,as it was replaced recently.
but then everything goes to normal after sometime.
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