RPM shoots up when changing gears

woodcrawler · 19th December 2012, 17:57

Quote:

Originally Posted by aaggoswami

Revs increasing suddenly without proportional throttle input is not normal. This is something wrong which somehow has found acceptance under the banner of many names. .....

Duster does not have this feature to the best of my knowledge, else this would come up in multiple reviews that I have read..... Sudden acceleration due to mats is not likely as it would actually hamper full flooring of throttle.......

The most likely possibility that comes to my mind is that the engine was cold and ECU was trying bring engine to operating temperature and hence increased the RPM. ......

Take the car to A.S & S. Duster is too new a product to research and arrive at conclusions. Its just not correct to have a car out of control due to unintended acceleration. There is something not correct, be it throttle pedal design, floor mat design or anything, but at the end of the day, this unintended acceleration must not happen ever again.

Thanks aaggoswami, The car is with the service guys right now, I'll get a clear reply tomorrow hopefully. I did not have a repeat of the spontaneous revving after that one incident. I guess you are right, it has been cold these days and I had just gone about a kilometer and had to downshift to overtake a bus that suddenly slowed down. Perhaps I depressed the clutch too suddenly, something I can't recall. I'll wait for the service center's verdict.

jaaz · 19th December 2012, 18:12

I had this problem in my old car in the 90's - Opel Astra. It's been a decade & half. Well the problem is the ECU. Please get it rectified at the Service Center. If it repeats again, try to get it rectified as soon as possible, since the vehicle is under warranty.

Catalyst_delhi · 19th December 2012, 22:01

In my ikon this was happening , It was an issue with the ground to the VSS , ECM and IAC , The shared a ground point and that was broken.

Just fixed a new ground point and back to stable idle and no hanging of rpms.

anupamsinha · 23rd December 2012, 00:16

Quote:

Originally Posted by 1self

You ARE supposed to lift your foot off the accelerator when changing gears. When you push the accelerator while changing gears, there will be a point when there is no load on the engine. Then the revs will rise suddenly.

Thanks for replying.

Yup, I do take of care of that.

First : When the RPM shoots then I do not depress the accelerator to an extent that it shoots up. So without the accelerator being depressed more than it was earlier it should not shoot.

Second : This problem is being noticed lately. So if it was related to my driving style it should have been there from day 1.

anupamsinha · 23rd December 2012, 02:46

Can't edit so another post.

Looks like its common but is disguised under another problem

http://www.team-bhp.com/forum/techni...pressed-4.html

anupamsinha · 3rd February 2013, 03:23

Got the issue fixed. It was the clutch.

Off late the suddenly the RPM would rise. Earlier it was after a gear change only. Moreover the pickup was gone. Decided to show it to the service centre as it was due for it's 3rd year and 20K service.

Got the clutch, pressure plate, flywheel, throw up bearing and a ball bearing changed.

Ball bearing and flywheel could have been reused but looking at the labour costs and individual price of the components I felt it would better if I got the whole thing changed.

Coupled with the service, with a 25% discount on labour (with some other things to be changed) the total cost came to about 8K. Out of which I guess clutch consumed around 5 - 6K.

Rolling_Stock · 4th May 2022, 14:35

Hi,

Need some advice here.
I drive Harrier XZA with 8000+kms on the ODO.

Of late, I have been experiencing a strange phenomenon while driving.
I notice the Engine RMP shoots up to a tune of +500rmp to +1000rmp and falls back to nominal value while shifting gears automatically during acceleration. I changed the modes to see if the behavior changes, but was the same.

I'm aware that this Torque converter has a slight rubber-band effect in the initial gears, which I'm used to, but the recent experiences were a bit more prominent in nature.
However, self or the family did not notice any sort of jerk during shifts, but my foot is sensitive enough to differentiate the behavior. There is clear sluggishness in the shift.

I do not see any fault indicators in the MID.
Is there a cause for concern ? or a premature ageing of clutch ?
If yes, let me know if I need to perform any specific diagnostics before reporting it to Service center ?

Cheers !!

19th December 2012, 18:12	#107
jaaz BHPian Join Date: Jul 2009 Location: Earth Posts: 661 Thanked: 636 Times	I had this problem in my old car in the 90's - Opel Astra. It's been a decade & half. Well the problem is the ECU. Please get it rectified at the Service Center. If it repeats again, try to get it rectified as soon as possible, since the vehicle is under warranty.
	() Thanks

19th December 2012, 22:01	#108
Catalyst_delhi BHPian Join Date: Oct 2011 Location: Noida/Coimbator Posts: 351 Thanked: 169 Times	Re: RPM shoots up when changing gears In my ikon this was happening , It was an issue with the ground to the VSS , ECM and IAC , The shared a ground point and that was broken. Just fixed a new ground point and back to stable idle and no hanging of rpms.
	() Thanks

23rd December 2012, 02:46	#110
anupamsinha BHPian Join Date: Mar 2006 Location: Delhi Posts: 118 Thanked: 57 Times	Re: RPM shoots up when changing gears Can't edit so another post. Looks like its common but is disguised under another problem http://www.team-bhp.com/forum/techni...pressed-4.html
	() Thanks

3rd February 2013, 03:23	#111
anupamsinha BHPian Join Date: Mar 2006 Location: Delhi Posts: 118 Thanked: 57 Times	Re: RPM shoots up when changing gears Got the issue fixed. It was the clutch. Off late the suddenly the RPM would rise. Earlier it was after a gear change only. Moreover the pickup was gone. Decided to show it to the service centre as it was due for it's 3rd year and 20K service. Got the clutch, pressure plate, flywheel, throw up bearing and a ball bearing changed. Ball bearing and flywheel could have been reused but looking at the labour costs and individual price of the components I felt it would better if I got the whole thing changed. Coupled with the service, with a 25% discount on labour (with some other things to be changed) the total cost came to about 8K. Out of which I guess clutch consumed around 5 - 6K.
	() Thanks

4th May 2022, 14:35	#112
Rolling_Stock BHPian Join Date: Nov 2021 Location: HOSUR Posts: 45 Thanked: 121 Times	Re: RPM shoots up when changing gears Hi, Need some advice here. I drive Harrier XZA with 8000+kms on the ODO. Of late, I have been experiencing a strange phenomenon while driving. I notice the Engine RMP shoots up to a tune of +500rmp to +1000rmp and falls back to nominal value while shifting gears automatically during acceleration. I changed the modes to see if the behavior changes, but was the same. I'm aware that this Torque converter has a slight rubber-band effect in the initial gears, which I'm used to, but the recent experiences were a bit more prominent in nature. However, self or the family did not notice any sort of jerk during shifts, but my foot is sensitive enough to differentiate the behavior. There is clear sluggishness in the shift. I do not see any fault indicators in the MID. Is there a cause for concern ? or a premature ageing of clutch ? If yes, let me know if I need to perform any specific diagnostics before reporting it to Service center ? Cheers !!
	() Thanks