[WilliamS]

Any of the XI guys running into this as well. I installed the JB4 today. Love it so far and on map 1 and map 2 I have an issue with the traction control trying to take my fun away. I cant feel wheel spin, it is an XI. As soon as I do the 5 second hold on the DTC button, all power all the time. What is tripping the traction control on the car even though its 4wd?

Map 1 will only do it from a stop or 5mph roll, Map 2 is up to about 50mph full throttle.

[psmitty95]

Originally Posted by Goofyguy

Any of the XI guys running into this as well. I installed the JB4 today. Love it so far and on map 1 and map 2 I have an issue with the traction control trying to take my fun away. I cant feel wheel spin, it is an XI. As soon as I do the 5 second hold on the DTC button, all power all the time. What is tripping the traction control on the car even though its 4wd?

Map 1 will only do it from a stop or 5mph roll, Map 2 is up to about 50mph full throttle.

What's making the traction control go off is wheelspin. Even though the car is xi that doesn't mean it will never lose traction. These cars modded have enough power and torque that they can still spin the tires on an xi

[WilliamS]

You are 100% correct. I may be all wheel drive, but I still do not have limited slip. Terry gave me that same info. So power is still trying to escape. I will say with DTC off the car is an animal. If there is some type of spin I cant feel it as the car just GOES. Coming from the Supercharged V8, I can now say Im very happy about the switch to the BMW. Man these cars just go with a passion.

Thank you for the response, it always helps to confirm all information when you a goof like me.

[psmitty95]

Originally Posted by Goofyguy

You are 100% correct. I may be all wheel drive, but I still do not have limited slip. Terry gave me that same info. So power is still trying to escape. I will say with DTC off the car is an animal. If there is some type of spin I cant feel it as the car just GOES. Coming from the Supercharged V8, I can now say Im very happy about the switch to the BMW. Man these cars just go with a passion.

Thank you for the response, it always helps to confirm all information when you a goof like me.

Hahaha no problem. I'm now used to just turning off all traction control everytime i start the car. When i used to forget i'd go to accelerate and then the car would stop me and it would get so frustrating

[giaolong]

I dont know how u are breaking traction though....if u really r, u need better tires.

I have 225/35 and 255/30 Toyo T1S on my car, even with JB4 + Map 7 + 50% E85 Gas, i launched the car as hard as possible with no problem at all with the Traction control on.

[WilliamS]

Originally Posted by giaolong

I dont know how u are breaking traction though....if u really r, u need better tires.

I have 225/35 and 255/30 Toyo T1S on my car, even with JB4 + Map 7 + 50% E85 Gas, i launched the car as hard as possible with no problem at all with the Traction control on.

The car was preped as a CPO but couldnt pass due to an accident. So it has runflats on all 4 corners. If they were not brand new I would ditch them today on road noise alone.

[psmitty95]

Originally Posted by giaolong

I dont know how u are breaking traction though....if u really r, u need better tires.

I have 225/35 and 255/30 Toyo T1S on my car, even with JB4 + Map 7 + 50% E85 Gas, i launched the car as hard as possible with no problem at all with the Traction control on.

I don't get how your not losing traction... . I'm running hankook ventus V12 staggered with JB4 map 5 and if i floor in in second gear i will occasionally lose traction and the car won't let me accelerate.

[amr_e90]

Originally Posted by psmitty95

I don't get how your not losing traction... . I'm running hankook ventus V12 staggered with JB4 map 5 and if i floor in in second gear i will occasionally lose traction and the car won't let me accelerate.

2nd gear now this is even more hard to believe then 1st gear, first off the cars about 3800 pounds and its not like its 20 degrees out that

[WilliamS]

Originally Posted by amr_e90

2nd gear now this is even more hard to believe then 1st gear, first off the cars about 3800 pounds and its not like its 20 degrees out that

On map 2 full thottle at about 20 will trip up my traction control and it basicly breaks my neck pulling power then going back on. DSC off with 1 push or is that tame mode, regardless it just pulls. I cant imagine slip at that speed but as it was pointed out to me, AWD sure but no limited slips front or rear so 1 tire is trying to light up.

Funny side note as the Dodge Durango in 2004 AWD didnt have limited slips either front or rear so if you full throttle from a stop, the front driver tire would light up! Hilarious to see in person.

[ajsalida]

Even with DTC/DSC full off you should still have e-diff (braking one wheel for electronic LSD) each axle and xdrive system allocating traction. You cannot turn those off. Something is not quite right here (broken from accident?), either that or you are on a very low friction surface.

edit: Had to look for this...


Automatic Differential Brake (ADB-X).
The Automatic Differential Brake (ADB-X) lets you make the most of your BMW's dynamic performance and sporting character on difficult road surfaces.

BMW's Dynamic Stability Control (DSC) system ensures that the vehicle remains stable when taking bends, speeding up or braking on uneven road surfaces or in poor driving conditions. The Automatic Differential Brake (ADB-X) is part of this system. Using sophisticated electronics, it offers the same function as a mechanical differential brake - without any disadvantages arising from weight and loss of efficiency.
If a wheel threatens to slip, it is individually braked: blocking momentum is directed to the wheel opposite, which thereby guarantees optimum drive power. When DSC or Dynamic Traction Control (DTC) is active, the engine power output is also adjusted.
If the sporting driver chooses to deactivate DSC or DTC, he still has the benefit of ADB-X, which then focuses on maximum forward drive and applies braking force only. A temperature control sensor ensures that the brakes do not overheat.

http://www.bmw.com/com/en/insights/t...erential_brake

[WilliamS]

Originally Posted by ajsalida

Even with DTC/DSC full off you should still have e-diff (braking one wheel for electronic LSD) each axle and xdrive system allocating traction. You cannot turn those off. Something is not quite right here (broken from accident?), either that or you are on a very low friction surface.

Braking is one thing, pulling power is another. Like I said, full throttle it hit full boost quick and pulls it just as fast. DSC 1 push and no issue from that side of things. I could still be keeping the wheels at speed by brakes but its not pulling power. Car is on factory Runflats and Florida roads arent known for clean or great surfaces.

[ajsalida]

Originally Posted by Goofyguy

Braking is one thing, pulling power is another. Like I said, full throttle it hit full boost quick and pulls it just as fast. DSC 1 push and no issue from that side of things. I could still be keeping the wheels at speed by brakes but its not pulling power. Car is on factory Runflats and Florida roads arent known for clean or great surfaces.

I am not understanding what you are asking about then. You have an e-LSD (and AWD) at all times, even with DTC/DTC full off. Are you asking why the DSC system pulls power when it's on? It senses the onset of wheelspin at any corner, which may be minuscule and below the threshold of driver awareness, and primarily cuts engine power to modulate traction. It also severely limits yaw/oversteer/understeer. One button touch and the threshold for cutting power is higher but the stability control is still there to a lesser degree (allows mild drifting), 5 sec press everything is gone except basic ADB-X and F/R transfer case. In other words you can spin all 4 wheels on low enough friction surfaces and do donuts.

[WilliamS]

Originally Posted by ajsalida

I am not understanding what you are asking about then. You have an e-LSD (and AWD) at all times, even with DTC/DTC full off. Are you asking why the DSC system pulls power when it's on? It senses the onset of wheelspin at any corner, which may be minuscule and below the threshold of driver awareness, and primarily cuts engine power to modulate traction. It also severely limits yaw/oversteer/understeer. One button touch and the threshold for cutting power is higher but the stability control is still there to a lesser degree (allows mild drifting), 5 sec press everything is gone except basic ADB-X and F/R transfer case. In other words you can spin all 4 wheels on low enough friction surfaces and do donuts.

I see where we were going.

With everything on as in started no pushing any buttons. On Tune 2 Full throttle as soon boost comes on full at low >50mph it will severly cut throttle and about rip your head off from the whiplash of on/off power. Im not turning, going sideways, hearing tires shred as it wouldnt being AWD. The car is sensing something in terms of wheel spin that I can not, and killing the throttle which is good and bad but its happening. One push of DSC so only DSC light on in dash and the throttle cut is gone, boost on Fuel verifys its staying at full power. If its braking to keep traction I know its faster than I would ever realize but at least its not pulling power and pushing me into the steering wheel.

My only question was where was I losing traction to have it shut down power. I got a message here and from Terry, that even with AWD the front and rear are still open diffs. So with all aids on becuase its not a limited slip when a tire starts to get squirrly it pulls power and applys some brake force to that tire. This confirms exactly what you are saying about DSC, with DSC pushed once I can power out without throttle cut, but the nannys are still there to keep from losing the car. I have no intent of a burnout, thats why I bought a X-drive.

[ajsalida]

OK I am glad that is sort of clear. The only thing is the answer from Terry is not entirely correct. The throttle shut down will happen whether you have a mechanical LSD or the e-diff if any slip is sensed. That is the "feature" of DSC. It cuts engine power first, or among the first things it does to prevent any wheel from spinning.

Imagine you replace the rear diff with a Qaiffe or whatever. Leave DSC full on. E-diff in front over an open diff, so each fronts can still spin subject to e-diff logic, the rears won't spin much relative to each other ever but front axle vs rear axle could slip.

Throttle will still be shut down either case subject to thresholds in the software. The only thing a mechanical diff in the rear will do with DSC on is mitigate situations in which throttle would have been cut where the DSC logic might have decided one rear wheel is spinning too much relative to the other rear wheel. I would not be surprised to find situation that DSC cuts power due solely to rear wheel spin even with a Qaiffe.

The Qaiffe is of course a much better LSD than e-LSD, but all the layers of DSC/DTC/ADB-X logic are still there and functioning even with a Qaiffe swapped in. So it is not so much open diffs at fault (you always have the ADB-X engaged on both axles even with the Qaiffe installed and DSC/DTC full off), it is the DSC logic that decides to cut power when it is engaged.

[psmitty95]

Originally Posted by Goofyguy

On map 2 full thottle at about 20 will trip up my traction control and it basicly breaks my neck pulling power then going back on. DSC off with 1 push or is that tame mode, regardless it just pulls. I cant imagine slip at that speed but as it was pointed out to me, AWD sure but no limited slips front or rear so 1 tire is trying to light up.

Funny side note as the Dodge Durango in 2004 AWD didnt have limited slips either front or rear so if you full throttle from a stop, the front driver tire would light up! Hilarious to see in person.

Exactly what happens to me