On a warmed-up engine, if the ECU goes open-loop during no-accelerator coasting above a given RPM, does that imply fuel cutoff?
I didn't believe my VW Cabrio implemented fuel cutoff, but I've been watching loop status lately and now I'm thinking I was mistaken. It seems to go open-loop any time the accelerator isn't depressed and the engine is spinning faster than about 1400RPM. (Interestingly, this happens whether the A/T is in drive or neutral.)
Just wondering if that's a sure sign fuel cutoff is happening. If so, I need to tweak my driving style slightly.
My car shows open loop under the same conditions you just described. You can also feel the car go out of fuel-cutoff into normal mode if you leave it in gear and let yourself coast down to below the RPM range. I feel a little shudder (and a reduction in deceleration) at the same time the Scanguage starts showing open loop, so I believe that is what it displays in my car.