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I keep messing around and noticing stuff on my Fit. I noticed that after I BUMP start it take a solid 7 sec before the ECU goes closed loop. Hey that's when I'm pulsing right.

Paul, I pulse as soon as I bump start in both the Elantra and the Insight -- no issues and I think my numbers speak for themselves.

I wouldn't idle it. You may get slightly better fuel economy in your pulse but you are splitting your FAS time with a NICE-ON -- you won't be able to make up the difference.

Are you reading this with a scangauge? There may be a sizeable
delay between when the feedback loop actually settles and when
the ECU finally deigns to tell you about it...
.
_H*

I believe this is intentional, and the sg is accurate. The factory service manual for my car confirms that the car when started always spends some time in closed loop operation. How long exactly is primarily a function of the coolant temperature. If the car is quite cold (initial coolant temperature of < 70 deg or so), it takes over a minute to get out of closed loop. If I shut off a warmed up car and start it again immediately, it takes about 10 seconds to go into closed loop.

I don't have a honda, but I'm pretty sure this is a universal behavior.

For what it's worth, my older Honda goes into closed loop almost immediately - maybe 2 seconds. From a cold start, it only takes about 10 to go into closed loop.

This is interesting because the Prius is obviously optimized
to go CL almost instantaneously, because it's always starting
and stopping. So it seems like some other engine/ECU setups
are not, since there's no expectation of too many on/off cycles,
meaning that a bunch of FAS and restart over a short distance
may wind up burning more fuel than expected. Depending on which
way open-loop tends to drift, of course...
.
_H*

TorqueNada takes about 20-30 seconds to go closed loop on a bump start. But then it seems to do everything slowly...

Paul, as I suggested above, I do not believe you can compensate for an added 7s NICE-ON glide in every P&G cycle.

Why don't you calculate what the fuel usage is during that NICE-ON by watching gph (note the RPM spike), then watch the GPH during your pulse. Do the same for pulsing open loop and just compare directly.

I think it's probably better to pulse in closed loop; generally open-loop operation runs a slightly richer mixture that closed-loop. But I'm sure it's not worth idling for 7 seconds to get to closed-loop every time you pulse.

Sort of like warming the engine up before you start driving. Yes, you get better FE in the early part of your drive. But you use much more idling the engine up to temp than you save from that better FE.

-soD