Go Back   Team-BHP > Under the Hood > Technical Stuff


Reply
 
Thread Tools Search this Thread
Old 7th December 2012, 15:51   #16
SUV
BHPian
 
SUV's Avatar
 
Join Date: Apr 2005
Location: BLR
Posts: 256
Thanked: 2 Times
Default Re: Missing Turbo Boost / Kick

I have been doing some research on this issue along with the help of a reputed Tuner in Blr.

Here is what we get to understand :

The EBCM (ABS Controller) might be faulty, which is why the ECU is limiting the Torque.

The ECU sends a Torque Request to the EBCM and if the EBCM reports that the wheel is spinning or the brakes are applied the ECU restricts the Torque (This is why we are seeing the Boost Pressure Intact and also the MAF readings to be normal).

Do any of you think this is a valid scenario ? I agree this principal applies to Car's equipped with TCS but would this apply in this case ?

I am going to Try Swapping the EBCM this evening, will post an update after that.
SUV is offline   (1) Thanks Reply With Quote
Old 7th December 2012, 16:00   #17
BHPian
 
Peter's Avatar
 
Join Date: Sep 2007
Location: Mumbai Goa
Posts: 205
Thanked: 45 Times
Default Re: Missing Turbo Boost / Kick

Quote:
Originally Posted by bhp_maniac View Post
If you can reproduce it, then its fine I believe. You can tell the same scenario to MASS, of course they might laugh first time Take 3 visits to MASS, one with tankful, then with the tank near quarter mark and the third time when it hits the last bar. Each time get an acknowledgement from them that your observation is correct. The underlying issue might be simple for them to diagnose.
Let me try that out ... Good one
Peter is offline   Reply With Quote
Old 17th December 2012, 17:05   #18
NMM
Newbie
 
Join Date: Feb 2007
Location: Bombay
Posts: 10
Thanked: Once
Default Re: Chevrolet Cruze - The case of the missing Torque / Turbo Boost ...

Quote:
Originally Posted by SUV View Post

The car picks up initial Boost (1300 RPM) till only about 2000~2200 RPM after which the boost stays flat and the rpm keeps climbing all the way to 4000 but the car doesnt move..
I have 2011 Cruze LTZ AT [ 34k + kms ]. I faced a similar problem very recently, when the accelerator was floored the car would pick up the initial boost then stay flat at around 4000 rpm. I checked with my service guy @ Ashtavinayak & he said it was probably because the air filter needed replacement & I was overdue for service by 2.5k+ kms. I just the car from service last week & my driver says problem seems to be fixed. I have been travelling so not checked it myself will do today evening ( will write a note if problem still persists ).The work done on the car was as follows :
1. Oil Change
2. New Air Filter
3. Brake Pads - front & back
4. Pending work - Ashtavinayak suggested I machine/repair my rear brake discs & replace the front discs. Wanted a second opinion before making that decision, I honestly found the estimate too high.
NMM is offline   Reply With Quote
Old 18th December 2012, 09:06   #19
BHPian
 
rocky080's Avatar
 
Join Date: Nov 2009
Location: Bangalore
Posts: 303
Thanked: 35 Times
Default Re: Missing Turbo Boost / Kick

Quote:
Originally Posted by SUV View Post
I have been doing some research on this issue along with the help of a reputed Tuner in Blr.

Here is what we get to understand :

The EBCM (ABS Controller) might be faulty, which is why the ECU is limiting the Torque.

The ECU sends a Torque Request to the EBCM and if the EBCM reports that the wheel is spinning or the brakes are applied the ECU restricts the Torque (This is why we are seeing the Boost Pressure Intact and also the MAF readings to be normal).

Do any of you think this is a valid scenario ? I agree this principal applies to Car's equipped with TCS but would this apply in this case ?

I am going to Try Swapping the EBCM this evening, will post an update after that.

Hey SUV any updates after changing the EBCM, did your power drop issue stop. I seem to be having a similar issue and my car does have Traction control. After reading your thread i noticed that the issue i am facing started after one of the wheel speed sensor was changed after it got damaged and have seen the TCS system come on even when the wheel is not slipping.

Please find the link tomy thread below:
http://www.team-bhp.com/forum/techni...ntra-crdi.html
rocky080 is offline   Reply With Quote
Old 18th December 2012, 09:18   #20
BANNED
 
Join Date: Dec 2011
Location: Chennai
Posts: 818
Thanked: 1,647 Times
Default Re: Missing Turbo Boost / Kick

Quote:
Originally Posted by yash.giri View Post

That sudden rush when turbo kicks in is completely missing in my car.
The Rapid’s engine has been designed so as to remove the sudden kick that one feels in the Vento and it is relatively more linear and depending on one’s driving characteristics it is possible to remove the kick completely.

However the undernoted scenarios should give you the kick:

1. Drive at a speed of 40 kmph in 4th gear , shift to 3rd and floor the throttle.

2. Drive at a speed of 20 kmph in 2nd, and floor the throttle.

3. Drive at a speed of 60 kmph in 4th gear and floor the throttle.

Autocar India Review on the Rapid “ The diesel has the kick of a mule.”

This remark from a team of seasoned test drivers who have experienced all sorts of turbo kicks says it all.
VeyronSuperSprt is offline   Reply With Quote
Old 18th December 2012, 10:03   #21
SUV
BHPian
 
SUV's Avatar
 
Join Date: Apr 2005
Location: BLR
Posts: 256
Thanked: 2 Times
Default Re: Missing Turbo Boost / Kick

Quote:
Originally Posted by rocky080 View Post
Hey SUV any updates after changing the EBCM, did your power drop issue stop. I seem to be having a similar issue and my car does have Traction control. After reading your thread i noticed that the issue i am facing started after one of the wheel speed sensor was changed after it got damaged and have seen the TCS system come on even when the wheel is not slipping.

Please find the link tomy thread below:
http://www.team-bhp.com/forum/techni...ntra-crdi.html
Regards to my Car, The Issue was resolved after a Turbo Change, Reflashing the EBCM and a ECU Update (in that order).

With regards to your specific issue, please calrify if they reset / relearnt the brake pedal position. This option is present in their diagnostic / programming tool. If not get it done and the problem should resolve.

If it still persists then check the wheel speed sensor which was replaced for correct alignment. Get it cleaned and go for a drive if the issue presists then have it changed (First try to swap it from another car to isolate the issue).

Note: Reset / Re-learn of the brake pedal position is very important after replacing the wheel speed sensor. This will also clear any DTC's present.
SUV is offline   Reply With Quote
Old 18th December 2012, 19:23   #22
BHPian
 
star_aqua's Avatar
 
Join Date: Aug 2008
Location: BLR
Posts: 612
Thanked: 88 Times
Default Re: Missing Turbo Boost / Kick

Quote:
Originally Posted by Peter View Post
Team,

This post tempts me to put across an issue I have observed in my SX4 Diesel ..

The Turbo boost is again ... another one of the main reasons for me to get this car as initailly experienced in the Test driven vehicle ( SX4 )

Enjoyed the Boost until it lasted , until recently what I have noticed is that the Boost is at its best only at certain levels of Fuel in the tank

Let me Explain , everytime I tank up to half tank the Boost is amazing , this continues till the Fuel indicator shows Quarter tank to empty.. this is where at times it seems as if there is no boost at all and continues to do so until the last Bar on the Fuel indicator and then suddenly returns back to normal ...then I tank up and the cycle repeats itself .

I know this may sound ridiculous but I have reproduced this issue N number of times ... funny thing is that I do not know how to put it across to MASS

Any Ideas ?
This could be the fuel tank breather getting blocked. to confirm, when ever you face the problem, just open the fuel tank lid or cap and close it. If the problem disappears, then it is because of vacuum buildup in the fuel tank.
star_aqua is offline   (1) Thanks Reply With Quote
Old 19th December 2012, 16:11   #23
BHPian
 
Peter's Avatar
 
Join Date: Sep 2007
Location: Mumbai Goa
Posts: 205
Thanked: 45 Times
Default Re: Missing Turbo Boost / Kick

Quote:
Originally Posted by star_aqua View Post
This could be the fuel tank breather getting blocked. to confirm, when ever you face the problem, just open the fuel tank lid or cap and close it. If the problem disappears, then it is because of vacuum buildup in the fuel tank.
Thanks star_aqua,

Will make this as the first check the moment the issue reproduces itself !!

So far the Torque is back at Quarter tank and its wicked and am enjoying it
Peter is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Turbo lag v/s Boost threshold Bookkeeper Technical Stuff 43 6th August 2015 23:39
Turbo Facts - How Much Boost In India? Psycho Modifications & Accessories 28 5th September 2014 22:48
DIY: Adjusting the Turbo Wastegate / Preload for More / Less Boost dhanushs DIY - Do it yourself 31 5th September 2014 01:05
Effective utilization of wasted boost pressure (Turbo) tsk1979 Technical Stuff 8 11th May 2013 14:30
Where Do I get BOOST? mazrx Modifications & Accessories 2 1st February 2005 11:40


All times are GMT +5.5. The time now is 05:35.

Copyright ©2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks