Team-BHP
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https://www.team-bhp.com/forum/)
Quote:
Originally Posted by Zappo
(Post 2904076)
3. Now the part that worries me most. Inspite of what M&M says I still idle my car after switch on (cold start) and before switch off. In fact I drive the last 500 meters or more at very slow speed at low RPMs so that the turbo is not used and then idle before the final switch off. And yet once the engine stops I hear a very faint freewheeling spin of something for quite some time everyday after parking. I have even tried to open the hood to check whether it's the fan that spins, ala Fiats. I don't think it's the fan. Then what is it that keeps spinning even after engine has been shut off? I need to find this out.
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Now this should not be happening atleast not in XUV. Mine does not do this, so i guess you have this checked asap. My Fabia does that, but i guess thats the fan that keeps working on even i have switched the engine off.
Quote:
Originally Posted by nitinralli
(Post 2904080)
Now this should not be happening atleast not in XUV. Mine does not do this, so i guess you have this checked asap. My Fabia does that, but i guess thats the fan that keeps working on even i have switched the engine off.
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Interesting. However, do note that this is a very faint noise and generally unnoticeable most times of the day. I only hear it at night when I enter my cellar parking which is absolutely silent, with almost nil ambient noise. In the day time my ears fail to pick up this spinning sound. You sure it's not there in other XUVs?
Quote:
Originally Posted by Zappo
(Post 2904083)
Interesting. However, do note that this is a very faint noise and generally unnoticeable most times of the day. I only hear it at night when I enter my cellar parking which is absolutely silent, with almost nil ambient noise. In the day time my ears fail to pick up this spinning sound. You sure it's not there in other XUVs?
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Atleast not in mine. Mine too is a cellar parking and i reach home late at night everyday (infact i am on my way to home rightnow) even then i didnt hear anything. Let me try to investigate it again today when i reach home, will post my findings tonight.
Quote:
Originally Posted by nitinralli
(Post 2904089)
Atleast not in mine. Mine too is a cellar parking and i reach home late at night everyday (infact i am on my way to home rightnow) even then i didnt hear anything. Let me try to investigate it again today when i reach home, will post my findings tonight.
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Please do. When I keep my ears tuned I hear two distinctive sounds. One prominent spinning sound that stops after 2 seconds of engine kill. The second one is the faint distant spinning sound that keeps coming, I think for the next 1 minute or thereabouts. Listen carefully if you can pickup any such sound. However the car shoul have run at around 1600 rpm at least for a good while in your journey.
Will check tomorrow for your observation.
Quote:
Originally Posted by Zappo
Please do. When I keep my ears tuned I hear two distinctive sounds. One prominent spinning sound that stops after 2 seconds of engine kill. The second one is the faint distant spinning sound that keeps coming, I think for the next 1 minute or thereabouts. Listen carefully if you can pickup any such sound. However the car shoul have run at around 1600 rpm at least for a good while in your journey.
Will check tomorrow for your observation.
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Ok i just reached home and checked, i couldnt find any sound when i parked. BUT, when i reach home, i have to wait for my gaurd to open the gate of my house, so it could be that while i was waiting for gate to be opened, fan or whatever that sound is, could have died down by that time. The moment i parked, i jumped out to hear something but nothing. And trust me, i have a real good pair of ears and can hear any sound that not even a human can pick up easily:)
Quote:
Originally Posted by Zappo
Please do. When I keep my ears tuned I hear two distinctive sounds. One prominent spinning sound that stops after 2 seconds of engine kill. The second one is the faint distant spinning sound that keeps coming, I think for the next 1 minute or thereabouts. Listen carefully if you can pickup any such sound. However the car shoul have run at around 1600 rpm at least for a good while in your journey.
Will check tomorrow for your observation.
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Is that sound like a leaked capacitor? I hear that sound in my beat D. There is no such sound in my XUV though.
Quote:
Originally Posted by Zappo
(Post 2904076)
Seriously? 1 lakhs for the turbo? Then again, it's quite possible since lighter turbos on much smaller engines cost close to 50k.
By the way, here are some observations.
1. M&M insists that you drive off gently after starting the car instead of idling
2. Unlike some of the earlier cars where they used to puta reminder plate with the engraved message about being a turbo fitted car and the necessary idling part there is no such thing anywhere on the XUV or in its manual
3. Now the part that worries me most. Inspite of what M&M says I still idle my car after switch on (cold start) and before switch off. In fact I drive the last 500 meters or more at very slow speed at low RPMs so that the turbo is not used and then idle before the final switch off. ...
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This is quite a confusing area to say the least. Few other vehicle including some Scorps still have the stickers about idling. XUV does not have it, neither does the manual mention it. Another point of view is that turbos are so costly precisely because they are extremely well-designed+precision-engineered and are much more tolerant and reliable as compared to previous generation turbos. I hope that's the case. Anyways, I am planning to be safe than sorry :p. Would continue to idle before starting and stopping after a long time.
Quote:
Originally Posted by Zappo
(Post 2904076)
...
I hear a very faint freewheeling spin of something for quite some time everyday after parking. I have even tried to open the hood to check whether it's the fan that spins, ala Fiats. I don't think it's the fan. Then what is it that keeps spinning even after engine has been shut off? I need to find this out.
....
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The infotainment system fan in XUV is known to be noisy and is typically heard for a few seconds after switching off. Might be that. Please check.
Quote:
Originally Posted by Zappo
(Post 2904076)
....
4. That Micro whatever they have to automatically shuts off the engine once you stop in traffic and lift off from clutch on neutral, how does that support a still spinning turbo?
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Thanks, that's a good point. You just gave me another reason not to use that useless Start-Stop/MicroHybrid. :)
Seeing above discussion, couldn't help but comment.
How is Turbocharger related and adversely affecting the Engine's Start/Stop function and its benefit, mainly fuel consumption control? Am I missing something?
Just one of the links on the topic "how turbo works" here:
http://auto.howstuffworks.com/turbo2.htm
Quote:
Originally Posted by parsh
(Post 2904183)
Seeing above discussion, couldn't help but comment.
How is Turbocharger related and adversely affecting the Engine's Start/Stop function and its benefit, mainly fuel consumption control? Am I missing something?
Just one of the links on the topic "how turbo works" here: http://auto.howstuffworks.com/turbo2.htm
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Experts can correct, here's my understanding: The turbo needs some lubricating oil for smooth operation which stops flowing once the engine shuts off. So we should let the turbo come to a complete stop before stopping the engine.
The question is: Does the start-stop feature which shuts down the engine at signals takes care of the turbo stopping before it shuts down the engine?
Edit: complete discussion ->
http://www.team-bhp.com/forum/techni...-shut-off.html
Quote:
Originally Posted by Zappo
(Post 2904076)
Seriously? 1 lakhs for the turbo? Then again, it's quite possible since lighter turbos on much smaller engines cost close to 50k.
By the way, here are some observations.
1. M&M insists that you drive off gently after starting the car instead of idling
4. That Micro whatever they have to automatically shuts off the engine once you stop in traffic and lift off from clutch on neutral, how does that support a still spinning turbo?
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Quote:
Originally Posted by SDP
(Post 2904143)
The infotainment system fan in XUV is known to be noisy and is typically heard for a few seconds after switching off. Might be that. Please check.
Thanks, that's a good point. You just gave me another reason not to use that useless Start-Stop/MicroHybrid. :)
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Clearly points of concern. Yesterday took delivery of my W8, & I had asked the guy same question regarding idling both before & after. He gave me some vague response, that being a VGT we can immediately switch the vehicle off. He said it is preferable to idle for some time, 30 secs, before staring the journey.
Now wrt to start stop function, it functioning negates the whole turbo idling debate. I'm concerned, What should I do? IMHO, found this function really nifty in the traffic snarls in COCHIN.
OT : Which is the idle rpm to shift gears, during running in? I find myself changing the gear at 1500-1600rpm. Have only run 130KMS till now. I have read the team-bhp running in post, it mentions speed of <80 Kms for first 200Kms and then, not to go above 2500-3000rpm till 1500Kms in case of diesels.
Idling before start is not required as per me.
Because turbo wouldn't be spinning at high speeds at idle. Only suggestion is to wait for the engine to reach optimal temp before gunning the turbo,which means 5 mins in to the drive.
Quote:
Originally Posted by SDP
(Post 2904197)
Experts can correct, here's my understanding: The turbo needs some lubricating oil for smooth operation which stops flowing once the engine shuts off. So we should let the turbo come to a complete stop before stopping the engine.
The question is: Does the start-stop feature which shuts down the engine at signals takes care of the turbo stopping before it shuts down the engine?
Edit: complete discussion -> http://www.team-bhp.com/forum/techni...-shut-off.html
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True. Sadly if this is going to limit the use of Start/Stop, how good a feature can it be, just a showpiece?
What I think:
1. Usually Turbo in car is primarily for boosting engine at higher speeds. There are small turbos also which operate on lower speeds but then those are useless for the primary need at higher speeds. Which is why also we see a small turbo lag in a car.
2. This is why it is advisable to idle for sometime after long speedy highway hauls so that turbo gets time to cool down its heels.
3. In city driving, the speeds are not going to be too high. Even if one does 80, it is not consistent and continuous. Thus there would not be too much of heating and worrying on that account. Also the new age turbo mostly employ liquid bearing technology (and even the solid bearing tech bearings are high temp withstanding ones) with the aid of lubricating oil cooling. So they are less of worry in regular city traffic.
4. Start/Stop function is becoming common across many levels of cars, small to biggies. I really hope and think they must have done quite a bit of R&D on these aspects to provide such a feature and thereby recommend using it.
NOW, pls dont go (mis)understanding why I am advocating/forcing this feature on you. It is not that way, it is just that the topic came up and I thought its a good point to start some thoughts and understand the core of it. I am also learning :)
Ideally this should have gone in the Turbo thread :) Sorry to hijack your thread.
Some nice debate. Let me put my 2 cents too.
While starting off:
You could wait for some 30 sec, but that is NOT going to get the vehicle to warm up. You definitely need to run couple of kms by when the vehicle warms up to proper operating temperatures. What we can all do is to drive slow & DON'T revv hard till this temperature is attained.
While switching off:
Well, if we are driving at high speeds, we need to idle the car to before we switch off the engine. This is basically to give the time for the turbo to cool off.
To clarify, don't we all run the car at low [crawling] speeds for atleast 30 seconds while reaching the office or a parking lot? There are hardly any instances where we come to a screeching halt from those speeds where the turbo is spooling & the car is switched off. This mostly takes care of the idling required.
Start/Stop in the traffic:
Well, I don't think we will be doing heavy speeds in the traffic right? In case we do it, what I suggest is to reduce the speed some 100 feet before you stop and bring your car to a stop by way of gearing which will ensure the rpm falls down to non-turbo rpm levels.
Otherwise, we could shift to neutral and keep your clutch pressed for that 30 seconds to ensure that the start/stop doesn't activate and you keep the car rolling till the red light.
I believe, we really don't get the turbo to be activated inside the city except for purely off-peak times, so no need to worry much about the turbo conking off due to start / stop system.
Quote:
Originally Posted by swiftnfurious Some nice debate. Let me put my 2 cents too.
While starting off:
You could wait for some 30 sec, but that is NOT going to get the vehicle to warm up. You definitely need to run couple of kms by when the vehicle warms up to proper operating temperatures. What we can all do is to drive slow & DON'T revv hard till
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Thats true but in xuv there is no way you can makeout that temp is perfect to rev it since the tem gauge only shows blue light all the time. Dont know why mahindra could not spend little money and have a simple method.
Couple of snaps from
a quick dash to Titwala yesterday (16th Sep 2012):
There was one more "MMI Zindabad" moment yesterday, when a critical turn on to a right route was not in the map at all and it took us through another route for 10 odd kms with quite bad roads. Anyways, lesson learnt: MMI can not substitute planning.
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Duma would go to Kaas on Wednesday. One day trip, possibly 550+kms to be covered in a single day. Would be a good test to check how comfortable the XUV5OO is for LONG drives.
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