Friends, while taking car from garage, initially at starting RPM shows 1000. After some driving it come below 1000 at starting. is it normal? Pl explain why it happens.
RPM : Speed : Gear Position
- Thread Starter sethumurugan
- Start date
1. Internal combustion engines perform best when they have reached their operating temperature.
2. On a cold engine, it takes time to reach operating temperature.
3. If the rpm is high, the operating temperature shall be reached more quickly.
4. Therefore, when a cold engine is cranked, the ECU raises the idle rpm slightly for some time in order to make the engine reach its operating temperature faster.
2. On a cold engine, it takes time to reach operating temperature.
3. If the rpm is high, the operating temperature shall be reached more quickly.
4. Therefore, when a cold engine is cranked, the ECU raises the idle rpm slightly for some time in order to make the engine reach its operating temperature faster.
+1 and to add to it, if your ac compressor is on , your idle will be higher at that point and will dip once the compressor cuts off. Most modern ECU's also periodically relearn idle - if you hear your car really closely once in a blue moon you might even notice this.
So i dont think its a cause for worry, unless its really erratic.
So i dont think its a cause for worry, unless its really erratic.
IMO, RPM meter in personal car is just for a reference to the user at what RPM the car engine is running.But RPM has some significant usage for the race car or rally car. Driver has to do some computation with RPM and accordingly need to change the gear or speed ![[confused]](https://www.theautomotiveindia.com/forums/images/smilies/Confused.gif "Confused [confused]")
. I don't know more on this.
I don't think so, we need to depend on the RPM to change the gear like race car driver do.
If you will see older car, they were not equipped with RPM meter. But now almost all car ,motorcycle comes with RPM meter.I would say this is just a style and your console will look good with some additional gadget.
. I don't know more on this.I don't think so, we need to depend on the RPM to change the gear like race car driver do.
If you will see older car, they were not equipped with RPM meter. But now almost all car ,motorcycle comes with RPM meter.I would say this is just a style and your console will look good with some additional gadget.
Last edited:
IMO, RPM meter in personal car is just for a reference to the user at what RPM the car engine is running.But RPM has some significant usage for the race car or rally car. Driver has to do some computation with RPM and accordingly need to change the gear or speed . I don't know more on this.
I don't think so, we need to depend on the RPM to change the gear like race car driver do.
If you will see older car, they were not equipped with RPM meter. But now almost all car ,motorcycle comes with RPM meter.I would say this is just a style and your console will look good with some additional gadget.
. I don't know more on this.I don't think so, we need to depend on the RPM to change the gear like race car driver do.
If you will see older car, they were not equipped with RPM meter. But now almost all car ,motorcycle comes with RPM meter.I would say this is just a style and your console will look good with some additional gadget.
RPM meter is mostly for the engine's behaviour. You can monitor the trend is raises at idle and when certain components you turn on. Apart from that some gear head might use it to do optimal gear shift.
RPM meter works in charm if you have a turbo charged or Vtec engine equipped cars. Reason is when you are on the track or road and some random ricer comes along and wants to do a drag.
my skyline's RPM meter I always used for perfect drag shifts in straight line . I used to Redline my R33 to around 7500RPM for every gear. 3rd gear would do 160 at this ratios.
FYI my car didnt have rev limiter
Last edited:
Any specific reason why petrol engines have an allowed rpm higher than diesels?
My nano's RPM exceed 2500 or so, and I was starting to get worried. I was assuming it as the primary reason for reduced fuel efficiency off late.
But in city driving, I think it is impossible to maintain such perfect RPMs. Anytime I see a two-wheeler comes my way, I need to slow and lower the gear. Again in order to maintain momentum and avoid honking from cars behind me, I have to press the gas pedal, thereby, taking the RPM to a higher value.
Great explanation; But, as I said above, very difficult to do so. More so in Nano, I found that the amount of energy to be spent on the acceleration pedal is quite high to make the vehicle catch with the crowd. Of course, lowering from 3rd to 2nd does help and it takes the RPM much above 2500.
I was searching for ideal RPM for nano and came across this post from our very own forum: http://www.theautomotiveindia.com/f...ws/6647-tata-nano-its-best-59.html#post234938
By the way, the reason I am suddenly reading about RPM and gears is because off late my FE has come down from 20+ in city to 17.8 (yesterday's fill), 18.5 (ten days ago) and 18.7 (about 20 days ago).
My nano's RPM exceed 2500 or so, and I was starting to get worried. I was assuming it as the primary reason for reduced fuel efficiency off late.
But in city driving, I think it is impossible to maintain such perfect RPMs. Anytime I see a two-wheeler comes my way, I need to slow and lower the gear. Again in order to maintain momentum and avoid honking from cars behind me, I have to press the gas pedal, thereby, taking the RPM to a higher value.
Great explanation; But, as I said above, very difficult to do so. More so in Nano, I found that the amount of energy to be spent on the acceleration pedal is quite high to make the vehicle catch with the crowd. Of course, lowering from 3rd to 2nd does help and it takes the RPM much above 2500.
I was searching for ideal RPM for nano and came across this post from our very own forum: http://www.theautomotiveindia.com/f...ws/6647-tata-nano-its-best-59.html#post234938
By the way, the reason I am suddenly reading about RPM and gears is because off late my FE has come down from 20+ in city to 17.8 (yesterday's fill), 18.5 (ten days ago) and 18.7 (about 20 days ago).
Wondering, how did I miss this thread? ![[surprise]](https://www.theautomotiveindia.com/forums/images/smilies/Surprise.gif "Surprise [surprise]")
Sam - Trust me, this is the best and simplest explanation I ever had. Thanks a million for bringing it here. That Cheetah & Elephant example was awesome and can make any dumb to understand the concept clearly.
Another killing explanation with simple examples. Hats off!
Yeah, the Egg thing was funny but very true. I have question on it though.
I drive Figo TDCi and I feel my accelerator is quite sensitive. Means, even a slightest touch makes the car to jerk. So I try to push it even lighter than a feather touch to avoid such jerks and have a comfortable drive. However, when I extend my leg a little more and press the pedal from the center of my foot, the jerk is noticeably lesser. What's wrong or right here?
BTW, I can feel a jerk even while taking the foot off the accelerator.
About the RPM, gear shift & FE - I always have heard, early upshifting is the key to achieve optimum FE. That means, one need to quickly climb the gears and not to revv much. On the other hand, maintaining the power band is also important for optimum FE. So, Aren't these too conflicting? While trying to upshift quickly, we may not reach the powerband (or) to maintain the power band we may either have to delay the gear shift or revv it a little more. Hope you get my question.
PS: In TDCi, Turbo kicks in as early as 1300-1400 RPM and Peak Torque is produced @ 2000 RPM. So if I believe it right, 1500-2000 is the power band.
Sam - Trust me, this is the best and simplest explanation I ever had. Thanks a million for bringing it here. That Cheetah & Elephant example was awesome and can make any dumb to understand the concept clearly.
Another killing explanation with simple examples. Hats off!
Yeah, the Egg thing was funny but very true. I have question on it though.
I drive Figo TDCi and I feel my accelerator is quite sensitive. Means, even a slightest touch makes the car to jerk. So I try to push it even lighter than a feather touch to avoid such jerks and have a comfortable drive. However, when I extend my leg a little more and press the pedal from the center of my foot, the jerk is noticeably lesser. What's wrong or right here?
BTW, I can feel a jerk even while taking the foot off the accelerator.
About the RPM, gear shift & FE - I always have heard, early upshifting is the key to achieve optimum FE. That means, one need to quickly climb the gears and not to revv much. On the other hand, maintaining the power band is also important for optimum FE. So, Aren't these too conflicting? While trying to upshift quickly, we may not reach the powerband (or) to maintain the power band we may either have to delay the gear shift or revv it a little more. Hope you get my question.
PS: In TDCi, Turbo kicks in as early as 1300-1400 RPM and Peak Torque is produced @ 2000 RPM. So if I believe it right, 1500-2000 is the power band.
Last edited by a moderator:
,by maruti driving school in facebook.
Can anybody explain.
Can anybody explain.
Hyundai Verna Fluidic Gear - RPM - Speed Issue
Hello Guys,
I need your help with this problem I am facing with my Hyundai Verna Fluidic 1.6 SX.
During my 3rd service(@20000 kms) a clutch overhaul was done since the clutch had become quite hard. I know the already existing issue with the clutch cylinder which the Verna models were facing since I had mine replaced a year back.
Since the service representative told me that I would only have to pay for the clutch disc(car is still under warranty) which is quite less compared to the overall procedure(around 15k) I thought why not do it. So the overhaul was done and after that the clutch became quite smooth![[clap]](https://www.theautomotiveindia.com/forums/images/smilies/Clap.gif "Clap [clap]")
and I was quite happy with the service till after a few days I started noticing there was something different. My car's gear-rpm-speed ratio has all changed .
What I mean is earlier my car would reach 80kph in 5th gear @1500rpm and now it is only reaching 70kph. For each gear changes like these are observed. My fuel mileage has also come down.
Any advice/suggestion on what could be the reason for this? I have been in and out of the service station 4 times in the last one month complaining regarding this issue and they are saying it is all correct and there is nothing wrong.![[frustration]](https://www.theautomotiveindia.com/forums/images/smilies/Frustration.gif "Frustration [frustration]")
Any Verna 1.6 SX owners, could you please tell me how your car's gear-rpm-speed ratios are?
Basically in each gear @1500rpm what the speed is?
Also the idling rpm too?
Procedures done during my 3rd service visit :
1. Clutch overhaul
2. Brake overhaul
3. Air filter replacement
Any help is highly appreciated. Please let me know if you need any further information.
Hello Guys,
I need your help with this problem I am facing with my Hyundai Verna Fluidic 1.6 SX.
During my 3rd service(@20000 kms) a clutch overhaul was done since the clutch had become quite hard. I know the already existing issue with the clutch cylinder which the Verna models were facing since I had mine replaced a year back.
Since the service representative told me that I would only have to pay for the clutch disc(car is still under warranty) which is quite less compared to the overall procedure(around 15k) I thought why not do it. So the overhaul was done and after that the clutch became quite smooth
and I was quite happy with the service till after a few days I started noticing there was something different. My car's gear-rpm-speed ratio has all changed . What I mean is earlier my car would reach 80kph in 5th gear @1500rpm and now it is only reaching 70kph. For each gear changes like these are observed. My fuel mileage has also come down.
Any advice/suggestion on what could be the reason for this? I have been in and out of the service station 4 times in the last one month complaining regarding this issue and they are saying it is all correct and there is nothing wrong.
Any Verna 1.6 SX owners, could you please tell me how your car's gear-rpm-speed ratios are?
Basically in each gear @1500rpm what the speed is?
Also the idling rpm too?
Procedures done during my 3rd service visit :
1. Clutch overhaul
2. Brake overhaul
3. Air filter replacement
Any help is highly appreciated. Please let me know if you need any further information.
First of all tell us do you have a petrol or diesel. I'll check on petrol what rpm is at 80kmph
I just checked. Rpm is 2000 in 5th gear at 80kmph.
I just checked. Rpm is 2000 in 5th gear at 80kmph.
Last edited by a moderator:
Nah. It should be the same for all diesel verma.