Quote:
Originally Posted by mstmng
yet it is another thread on drive train malfunction, but a bit different, as i need to decide ASAP whats the next step i should take to try and fix it.
I am running a tune with 705BHP and 920NM torque
i have no issues on everyday basis use, however when i go out on autobahn/airfield and go WOT in any mode (efficient/sport/sport+) soon as rpms get to 5-5.5k i get misfires and if i dont let off the throttle immediately or change to next gear i get CEL (sometimes blinking (it is different from when it is just there)), drive train malfunction and power loss. Soon as i stop, turn the engine off, turn it on, power is back, d t mal is gone and CEL needs to be cleared obviously.
yesterday i had 1000-mile drive and i was trying to figure out if this happens only under WOT or not, so i did manage to get to 7400rpms in 4th without getting any errors under 1/2 - 3/4 of throttle but then i got all the issues under 1/4-1/2 throttle in 5th gear coming to 5500 rpms
i have never had this issue with catless DP's and NO tune, catless dp's and BMS with NO can tool, so logically thinking it is caused by ECU tune and my tuner clearly does not know what the issue is, as he never tested car under WOT and under slowly acceleration he got to 190mph on dyno and car been with him twice already
HOWEVER, my mechanic at bmw did all the tests and checked my spark plugs and coils and there were misfires in the memory of all 8 cylinders obviously and code: 118111 Mixture control 2, cross-bank: Fuel-air mixture too rich, but fuel-air fault appeared twice at 0 rpms and 760 rpms in other words at the time of engine being off and then at idling
so he said fuel-air issue in definitely a software issue and 100% related to my tune, however d t mal/cel/power loss might be to do with turbo actuators! as early e9* 335's had exact same issue with d t mal, cel, power loss under WOT above 120mph and bmw couldnt understand what the issue is, but eventually they changed actuators and issue was gone.
also i get misfires/d t mal and CEL when i start the car after 24h of not using it, then i need to turn it off, start again couple of times and then it is gone!
i have no problem changing actuators, however do i need to spend $$ and mine and my mech's time ? my car going back to tuner tomorrow and i want him to play around with timing between 5k rpms and redline, however if anyone had exact same issue and knows exactly what needs to be adjusted please let me know here or PM me... i am quite desperate to fix it, as i have airfield event coming on saturday and so many super/hypercars coming there, but unless my car is fixed, no point going there and then i have to wait till end July for next event
i wanted to drive down to Br and get a tune done there before saturday, however they told me next available appointment is 6-7 weeks away and it is kind of pointless for me to pay twice for more or less same tune, when i am sure solution is there and it is easy, it is just my tuner does not know exactly what needs to be done
any input would be highly appreciated!
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What I have picked up is that this issue seems to be happening to cars with more aggressive tuning and downpipes.. I have had a BR PERFORMANCE tune since January.. I can run my car to the max in any gear WOT .. No dtmal.. Yesterday I ran my car through to a town on back roads here in CA and specifically drove hard to see whether I could cause a dtmal. Not once.
What I am saying to you is I suspect it's got to do with the remap down pipe combination somehow. Bone stock I am dynod at 612 whp. At 15% correction factor I'm in your ballpark for hp.
Every person who I have spoken to who has the issue has both downpipes and the more aggressive remap combo. I can't say with 100% certainty.. But that has been my experience..
I think the best thing to do is to get your remap customized by your tuner and go from there..if that doesn't work..maybe head to BR?
If I still lived in London, I would make the trip just because I am confident BR could sort it out with your car there on their Dyno.