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Old 8th January 2017, 14:53   #16
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Default Re: Strange issue with acceleration

Sometimes the engine does tend to idle at higher rpms in the event of a cold start.
When it's cold, combustion requires much more fuel in the air fuel ratio because it does not sufficiently vaporize from liquid into a gaseous form. Too much fuel through the engine at a low speed will cause it to stall. Hence the ecu bumps the acceleration to push fuel out more quickly until a desirable temperature is attained. Once warm enough, the fuel vaporizes as it should, the ecu dials back the fuel mixture and the rpms come down. Now this might be the issue you are facing since the problem doesn't return throughout the day.

Last edited by Samurai : 8th January 2017 at 17:26. Reason: typo fixed
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Old 8th January 2017, 16:34   #17
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Default Re: Strange issue with acceleration

So, keeping engine on for sometime should help ? What I observed was I had to stop the engine for sometime and start again to get rid of it...
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Old 8th January 2017, 17:10   #18
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Default Re: Strange issue with acceleration

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Originally Posted by Revention View Post
So, keeping engine on for sometime should help ? What I observed was I had to stop the engine for sometime and start again to get rid of it...
A little more insight on your issue would be helpful. The phenomenon i stated in the previous post happens only when the car is left to idle or coast, You will notice a slightly higher idling rpm which settles down once the temperature is reached and its normal. This doesn't hamper driving and is not intrusive of any sorts.

Would like to know if your issue is the accelerator pedal getting stuck or the engine rpm being held after accelerating the vehicle like for eg. if you rev the vehicle to 2k rpm does the rpm get held in that region itself? if so i would suggest you get it checked at ASS might be the accelerator cable or a faulty sensor. if its just a higher idle rpm i wouldn't be worried considering Bangalore does get pretty cold.
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Old 8th January 2017, 18:29   #19
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Default Re: Strange issue with acceleration

Does your car have an RPM meter? Have you noted what would be the RPM reading when the idle is raised? During cold start the MPFI cars do have an idle compensator which will raise the RPM by about 200-300 RPM to aid faster heating of engine to operating temperatures. This is normal.

Only if this raised RPM prolongs for more than few minutes/ the engine temperature starts to climb, then you need to check the throttle body. Throttle body idle circuit there would be a stepper system that would need a clean up.
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Old 8th January 2017, 18:43   #20
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Quote:
Originally Posted by Jaggu View Post
Does your car have an RPM meter? Have you noted what would be the RPM reading when the idle is raised? During cold start the MPFI cars do have an idle compensator which will raise the RPM by about 200-300 RPM to aid faster heating of engine to operating temperatures. This is normal.

Only if this raised RPM prolongs for more than few minutes/ the engine temperature starts to climb, then you need to check the throttle body. Throttle body idle circuit there would be a stepper system that would need a clean up.
Will check the RPM reading if it happens tomorrow morning.
The raise lasts only few seconds (max 4-5) , everytime, but is unnerving even then...
Also this is something I never encountered in past 8 years

Quote:
Originally Posted by blackbandit View Post
A little more insight on your issue would be helpful. The phenomenon i stated in the previous post happens only when the car is left to idle or coast, You will notice a slightly higher idling rpm which settles down once the temperature is reached and its normal. This doesn't hamper driving and is not intrusive of any sorts.

Would like to know if your issue is the accelerator pedal getting stuck or the engine rpm being held after accelerating the vehicle like for eg. if you rev the vehicle to 2k rpm does the rpm get held in that region itself? if so i would suggest you get it checked at ASS might be the accelerator cable or a faulty sensor. if its just a higher idle rpm i wouldn't be worried considering Bangalore does get pretty cold.
No , its not when left to idle, but when driving and when pedal is pressed.
So its intrusive ( I press clutch immediately for safety)
I did suspect the pedal, but the way it goes off after car restart and never happens again throughout the day, makes pedal issue much doubtful.
I haven't checked RPM reading, which I will do tomorrow, but I believe it must be rising over what I pressed for ....

Last edited by Jaggu : 9th January 2017 at 10:46. Reason: Back to back posts, please use Multi Quote [Quote +] or Edit original post to add reply. Thanks.
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Old 8th January 2017, 19:32   #21
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Default Re: Strange issue with acceleration

Quote:
Originally Posted by Revention View Post
No , its not when left to idle, but when driving and when pedal is pressed.
So its intrusive ( I press clutch immediately for safety)
I did suspect the pedal, but the way it goes off after car restart and never happens again throughout the day, makes pedal issue much doubtful.
I haven't checked RPM reading, which I will do tomorrow, but I believe it must be rising over what I pressed for ....
As per your description it does seem like the issue is of the accelerator cable assuming swift petrol is not equipped with drive by wire. Dirt or fraying(must be dirt in your case) of the cable can cause the accelerator to get stuck for a very short period and return back to normal. You not seeing the issue later through the day might be due to the dirt freeing up on usage. The problem going off after a restart might be a pseudo feel in my opinion, it might be that the accelerator returned to its normal position by the time you restarted. Would suggest you to get it checked and cleaned or changed if the issue persists or has occurred multiple times recently.

Anyways do note the readings and post your observations.
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Old 9th January 2017, 10:48   #22
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Default Re: Strange issue with acceleration

Quote:
Originally Posted by Revention View Post
The raise lasts only few seconds (max 4-5) , everytime, but is unnerving even then...
Also this is something I never encountered in past 8 years
====
No , its not when left to idle, but when driving and when pedal is pressed.
So its intrusive ( I press clutch immediately for safety)
Seems like a faulty acc cable as others mentioned or the throttle body idle controller getting stuck momentarily. Try to take a video of the phenomenon on your phone, that will make it easy to explain at service center.
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Old 9th January 2017, 11:19   #23
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Default Re: Strange issue with acceleration

Quote:
Originally Posted by Revention View Post
Hi all,

I have a strange issue with my 2008 Maruti Swift ZXi.

Thanks!
I have the same issue in my 2010 Alto K10.
This issue comes up when i drive in rains too. It feels like there is some play in 'A' pedal, but it is not says my SA.
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Old 9th January 2017, 11:23   #24
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Default Re: Strange issue with acceleration

Quote:
Originally Posted by Revention View Post
Hi all,

I have a strange issue with my 2008 Maruti Swift ZXi.
In the mornings, which I start the car first time, the accelerator has a strange issue. For first few 1-2 kms , the raise seems to "stick" for sometime
I had similar issue in my Santro around 6 months ago. Like many others have said, it was the sticky accelerator cable that was the cause. I did the below experiment and the issue was gone.

Suggest you do the following to validate whether it is accelerator cable issue: Two people are needed to do the below exercise. If this does not solve the problem, you can consult ASC.

1. Before starting the car, Open the bonnet and stand in front of bonnet.
2. Ask the second person to press the accelerator repeatedly(Car should NOT be started. Suggest do not even insert the ignition Key to be on safer side !)
3. When the second person presses the cable, you can observe one lever moving near the engine
4. Once you locate the exact lever, you can directly grease the lever and put some oil inside the cable outer.

I think and wish this will solve the issue.
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Old 9th January 2017, 12:05   #25
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Default Re: Strange issue with acceleration

Didn't happen today ! Maybe happens with longer gap in the cold starts...
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