Has anyone with a 7 speed DCT experienced anything like I'm describing below?
I bought my car in 2019, it had come off lease. I've only used launch control 8 times, at the track in spring 2022. Being that it's a lease return, perhaps the previous driver launched the crap out of the car. (?) 48k miles. The tranny is tuned with xHP stage 2.
Last year I began noticing the occasional "free rev" between gears 1-2, prior to taking it to the track. The first time was slowly driving through a parking lot during the 1-2 shift in "D" mode. Light pressure on the throttle and the car rev'ed to 2500-3000 rpm between gears, got off the throttle and proceeded in 2nd. I experienced the same behavior driving through our neighborhood. Occasionally the same occurs between 2-3, always with light throttle.
Post modification, the car also has the occasional hard time idling, hunting for the idle target, and will sometimes die at a stoplight while sitting around 750 rpm. I went through some tune iterations with Wedge hoping that the idle issue could be addressed, but so far no luck. I've got a BMS BOV kit, which allows unmetered air into the loop while idling, and BMS has assured me it should not affect idle. This has caused me to think about the interface between the input shaft/TCM/clutches/DCM, and if something may be borked in the tranny / power train. There's also the occasional thunk when engaging reverse, which isn't something I enjoy.
That initial tap of the throttle to get the transmission to engage does occasionally cause the car to surge a bit, more than I'd expect.
So I'm planning to have my local indy shop (ex BMW tech has his own business, he's done a fair amount of work for me and other enthusiasts in the area) drop the transmission & determine if anything is amiss. While the tranny is out the clutches should probably be replaced with something that'll be better at holding the 675 lb/ft. Dodson is big $$, other recommendations for aftermarket clutches?
Thanks.
I bought my car in 2019, it had come off lease. I've only used launch control 8 times, at the track in spring 2022. Being that it's a lease return, perhaps the previous driver launched the crap out of the car. (?) 48k miles. The tranny is tuned with xHP stage 2.
Last year I began noticing the occasional "free rev" between gears 1-2, prior to taking it to the track. The first time was slowly driving through a parking lot during the 1-2 shift in "D" mode. Light pressure on the throttle and the car rev'ed to 2500-3000 rpm between gears, got off the throttle and proceeded in 2nd. I experienced the same behavior driving through our neighborhood. Occasionally the same occurs between 2-3, always with light throttle.
Post modification, the car also has the occasional hard time idling, hunting for the idle target, and will sometimes die at a stoplight while sitting around 750 rpm. I went through some tune iterations with Wedge hoping that the idle issue could be addressed, but so far no luck. I've got a BMS BOV kit, which allows unmetered air into the loop while idling, and BMS has assured me it should not affect idle. This has caused me to think about the interface between the input shaft/TCM/clutches/DCM, and if something may be borked in the tranny / power train. There's also the occasional thunk when engaging reverse, which isn't something I enjoy.
That initial tap of the throttle to get the transmission to engage does occasionally cause the car to surge a bit, more than I'd expect.
So I'm planning to have my local indy shop (ex BMW tech has his own business, he's done a fair amount of work for me and other enthusiasts in the area) drop the transmission & determine if anything is amiss. While the tranny is out the clutches should probably be replaced with something that'll be better at holding the 675 lb/ft. Dodson is big $$, other recommendations for aftermarket clutches?
Thanks.
