01-23-2015, 10:16 AM | #1 |
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Miss Shift (Auto 8SP)?
I had an extremely odd, yet uneventful transmission miss (I think).
Yesterday, while turning right off a street the car seemed to go into neutral and the RPM's spun up. Well, that's what I think happened. It was fast. I turned, car reved up, I looked and saw the RPM at around 5000, then looked at gear indicator, and tried to pay attention for TCS. The moment I engaged the gas a moment later (at around 2500 rpm) the car pulled away normally with traction. I didn't notice any shifting or alteration in the cars dynamics or feel. I did NOT have my hand on the shifter. I was accelerating slowly after the turn, not in the turn (relatively speaking). I lifted my foot off the gas as soon as the RPM spiked. The TCS light did NOT come on (as far as I noticed). The car did NOT yaw or slide as you would expect. I never felt the car shift down or up around the event. The gear indicator always showed "D" (again, as far as I can tell). Its entirely possible that the spin up was actually a "slip". The roads were wet/icy. But as I said, the car didn't slide or yaw and that the TCS didn't engage as far as I can tell. I'm willing to accept that both wheels spun exactly the same amount and at the same time. This has never happened before, mostly had sticks before this. |
01-25-2015, 07:44 PM | #2 |
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If the transmission seemed to have disconnected (Feeling like it's in neutral), and the revs shot up to around 5,000.. seems to me like you activated launch control. Are you a left-foot braker?
Nothing in the car's traction/stability system allows the car to rev that high under loss of traction situations (assuming TCS is on) |
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01-26-2015, 09:17 AM | #3 |
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The car was doing around 15-20 mph when it happened, can you active LC at that speed?
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01-27-2015, 09:59 AM | #5 |
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Drives: 2019 G30 M550i
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DSC/TCS will not go off if it does not need to, i.e. it expects a slip to not get out of control.
I would not worry about it right now until it happens again and not in an icy situation.
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01-27-2015, 02:02 PM | #6 | |
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Quote:
This. I wouldn't take it to the dealer just yet. I'd wait to see if it does it again. You might've just had some weird ordeal where one wheel slipped and the car reacted in a way that brought a lot of attention to what happened. |
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