SMG occasional slow downshift 4-3 in auto mode

[aaronjb]

Hi All,

I've had my E36 M3 Evo SMG for a few weeks now and a couple of times I've noticed it'll seem to get all confused when downshifting from 4-3 or 3-2 when in fully automatic mode, for example when I'm coming up to a roundabout and then give it some throttle to nip out in front of traffic.. it's a little disconcerting to hear it drop to neutral and do it's little 'misfire' sound (which I assume is normal, it seems to do it between all automatic changes as if that's how the ECU does torque reduction to keep the clutch happy?) and then.. you're coasting until it finds the right gear again.

Any clues what that might be? It only ever does it in automatic mode (E or not) and yet in manual mode the changes are perfect every time (if a little slower than I could manage with my left leg and arm in a manual ;)).. which I presume means it's more likely a sensor than the SMG pump/accumulator (which were replaced just prior to my purchase)..

Thanks,
Aaron

[jamie123]

have you checked the fluid?
you might get more answers on a uk based forum mate as the smg wasnt available in the states. try m3cutters.com.

[98m3estoril]

its having trouble slotting in a gear which means you are probably down on hydraulic pressure. you can check that if you hook up the right bmw computer. other than that, could be a myriad of things. the smg relay is often blamed & is a cheap replacement so could be a good place to start.