Drivetrain malfunction, car wouldn't go past first gear

Finley · 01-18-2026, 01:20 PM

F8x DCT transmission codes, drivetrain malfunction
I was coasting on the freeeway and had to brake to first gear due to traffic. Showed drivetrain malfunction and car wouldn't go past first gear. Happened twice already, codes attached. I'm on MHD stage 0 and Original transmission tune. I have downpipes as the only mod.

Finley · 01-18-2026, 01:21 PM

I had the DCT serviced last year at S5x Performance in February at 69k miles car currently has 81k miles. Replaced the fluid and filter.

vertea · 01-20-2026, 01:25 PM

You'll definitely need ISTA to diagnose this. Hopefully it's a sensor issue, but if there's a stuck master/slave cylinder causing it to stick that'll be a lot of $$$$.

01-18-2026, 01:20 PM	#1
Finley Registered 0 Rep 2 Posts Drives: M4 Join Date: Jan 2026 Location: California iTrader: (0)	Drivetrain malfunction, car wouldn't go past first gear F8x DCT transmission codes, drivetrain malfunction I was coasting on the freeeway and had to brake to first gear due to traffic. Showed drivetrain malfunction and car wouldn't go past first gear. Happened twice already, codes attached. I'm on MHD stage 0 and Original transmission tune. I have downpipes as the only mod. Attached Images Last edited by Finley; 01-18-2026 at 01:25 PM..
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01-18-2026, 01:21 PM	#2
Finley Registered 0 Rep 2 Posts Drives: M4 Join Date: Jan 2026 Location: California iTrader: (0)	I had the DCT serviced last year at S5x Performance in February at 69k miles car currently has 81k miles. Replaced the fluid and filter.
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01-20-2026, 01:25 PM	#3
vertea Enlisted Member 24 Rep 31 Posts Drives: '18 M4 ZCP, '20 X3 M40i Join Date: Nov 2025 Location: New Jersey iTrader: (0)	You'll definitely need ISTA to diagnose this. Hopefully it's a sensor issue, but if there's a stuck master/slave cylinder causing it to stick that'll be a lot of $$$$.
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