Hi guys. Bought a 2003 CVT Mini with a trans that wouldn't shift after warmup. Bought a parts car with what was supposed to be a good CVT but a blown engine. Swapped CVT's dropped it off to a trusted indy Mini/BMW shop to do the fill and initialization. They said they couldn't fully finish do to a suspected iffy shifter. The shop said the module was fine.
Drove fine for the 1st 20m, then started behaving erratically and slipping after a brief test drop and stop. Question - can a bad shifter sensor (not module) cause this? Before I give up and buy another parts car with a good manual trans and engine, thought I'd ask here. The shop isn't sure a shifter change would fix it. I'm guessing not.
Thanks for any input, Ron

Most change the fluid, https://www.northamericanmotoring.co...n-fluid-431057


Not many things can be replaced on it

https://www.ecstuning.com/Mini-2004-...Transmission/2



I would get a Schwaben scan tool and scan it. See what codes come up.

https://www.ecstuning.com/b-schwaben...020sch01a~scf/

Thanks for the reply. Fresh fluid fill but they couldn't fully initialize it due to an apparently iffy shifter. Could it be slipping from neutral to D from a bad shifter switch?

Could be, i would tear into the shifter itself, disconnect it from the transmission and see if it moves freely.

The shifter moves freely but maybe not sending a clear signal. Belts wear gradually (usually) - yes? Didn't notice any metal from either trans when draining fluid during the swap. Might end up swapping to a manual, but aren't going to keep it and want to keep my time in it to a minimum. Was just supposed to be a fun project Have a manual 2005 r50 that's my main ride.