[woodex m.e.]

I have a 2007 335xi with a manual transmission and am having a bit of an odd problem with it. I bought it a few weeks ago and drove it home on the stage 2 tune (MHD tuner) and it ran great. Very stout. I did a bunch of little things on it like fix suspension and brakes and such for a few days and then mapped it to stage 1 before I took it out, since its not set up for 2.

On a regular occurrence such as a long on-ramp or a freeway pull in 3rd gear (sometimes 4th) I will near 5k rpm and then it will close the throttle body while I'm to the floor. This makes the car feel like its stalling out. This isn't some slight closure either. My pedal will be floored and the throttle will go from 81% to something like 10% in a few fractions of a second. (I have found it will now do this with both stage 1 and 2 tune on, even on the lower octane setting)

The logs I have say that I'm activating a torque limit? I don't really know what that is about and that's the exact moment the throttle starts to close. I don't know much about timing, but it does retard timing a little before the closure. By about 2-3deg. across all cylinders. As the throttle closes the timing comes back.

Anyone experienced this? Most the other threads I have found relating to this involve a torque limit (AT only) or slight closures in throttle, not full.


https://datazap.me/u/woodex-me/3rd-g...og=0&data=3-21

[Jeff@TopGearSolutions]

I'd contact MHD. May be something simple in the tune they need to adjust with regards to torque limiters.

Assuming you have already downloaded the latest maps? If not, try those first.

[woodex m.e.]

Originally Posted by Jeff@TopGearSolutions

I'd contact MHD. May be something simple in the tune they need to adjust with regards to torque limiters.

Assuming you have already downloaded the latest maps? If not, try those first.

Sweet jesus a reply!

Thanks, maybe ill try that. I got it 2nd hand and just have what came on it. I have it on v8beta right now. Does the same thing on v7 as well. It did do an update just the other day. Not sure if that will affect it. I can try loading the update.

Sounds like those guys are good with customer support?

[RSL]

Limiter 1 is traction control and at least 1 other torque cap that I know of, but your calculated torque isn't close to that. You could try the same acceleration with traction control all the way off and see if it does it. Could be something as simple as a flaky wheel speed sensor indicating slip and falsely triggering DTC. There could be other sensors for center diff/AWD too that I'm not aware of, but if it doesn't do it with DTC off, you'll have narrowed down what to look for. Very much doubt it has anything to do with an OTS map.

[woodex m.e.]

Originally Posted by RSL

Limiter 1 is traction control and at least 1 other torque cap that I know of, but your calculated torque isn't close to that. You could try the same acceleration with traction control all the way off and see if it does it. Could be something as simple as a flaky wheel speed sensor indicating slip and falsely triggering DTC. There could be other sensors for center diff/AWD too that I'm not aware of, but if it doesn't do it with DTC off, you'll have narrowed down what to look for. Very much doubt it has anything to do with an OTS map.

All good stuff, but sadly that run was with DTC fully disabled. It does it when on or partial as well.

[RSL]

Hmm. I still might not rule out something with the AWD system working through DSC and DTC logic that isn't actually DTC. I don't know enough of the Xi system to point to anything specific though. I do know they are much more finicky with calculated torque though. Have you tried a v8 OTS map to see if there is any change?

[woodex m.e.]

Originally Posted by RSL

Hmm. I still might not rule out something with the AWD system working through DSC and DTC logic that isn't actually DTC. I don't know enough of the Xi system to point to anything specific though. I do know they are much more finicky with calculated torque though. Have you tried a v8 OTS map to see if there is any change?

Yeah i dont know enough about it either. I have tried 7 and 8. It does it on anything other than stock power level. Even then you can still see partial closures just not enough to feel. But from what i understand thats typical.

But it only does it in 3rd or 4th gear never 1st or 2nd. I know it spends a lot less time in each of those gears but still.

[RSL]

Everything drops, including requested load, so definitely seems like an intervention or limit is being called. AWDs are real particular about calculated torque, but yours doesn't look that high. No limp modes or codes when this happens?

If it just occurs with no errors logged, Jeff is probably right, contact MHD Tuning and have them take a look.

[woodex m.e.]

Originally Posted by RSL

Everything drops, including requested load, so definitely seems like an intervention or limit is being called. AWDs are real particular about calculated torque, but yours doesn't look that high. No limp modes or codes when this happens?

If it just occurs with no errors logged, Jeff is probably right, contact MHD Tuning and have them take a look.

No codes, no chimes, no warnings....just shuts the throttle plate. Thanks for looking, Its a big help to get another opinion.

I will drop them a note and see what they say.

[woodex m.e.]

Dropped MHD a note and did get a reply. They said its normal, but I think they miss understood my problem that the throttle was closing fully not slightly as typically seen. I clarified so hopefully I get an answer back and can post it here to help someone else in the future.

Wasn't running logs today, but it happened prety bad. Was on the highway and went to accelerate and got nothing in 4th 5th or 6th. Waited a few seconds and tried again and it went fine. Odd stuff.

[B335T E92]

Originally Posted by woodex m.e.

Dropped MHD a note and did get a reply. They said its normal, but I think they miss understood my problem that the throttle was closing fully not slightly as typically seen. I clarified so hopefully I get an answer back and can post it here to help someone else in the future.

Wasn't running logs today, but it happened prety bad. Was on the highway and went to accelerate and got nothing in 4th 5th or 6th. Waited a few seconds and tried again and it went fine. Odd stuff.

Literally, the same exact problem on my XI. I was thinking a pro tune will get me sorted. What did you find out from Martial?