High/low load Closed Loop Crossover

2012+ US/Canadian Civic Si / 2013+ ILX
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bigbadspoon
Posts: 34
Joined: Wed Mar 13, 2013 3:20 pm

High/low load Closed Loop Crossover

Post by bigbadspoon »

So, I've been running a tune lately that will go lean during low load/cruise, which it does quite well and has been achieving great mileage, *but* it doesn't seem to cross down to the high load setting when accelerating onto the highway, etc.

In the Flashpro documentation, the info on the closed loop tables indicates a crossover point somewhere around 50 kPa, but that doesn't seem to be the case, based on my logs (one is attached; highway entry at about 14:05 to about 14:30).

So, I guess my question is: is it not actually crossing over to the high load table? Or, is it crossing over too slowly to really go down before I let off the gas and go into low load, then shift, and lay back into it? Or, does it interpolate the value somewhere between the high and low load tables? If so, is it possible to tune the crossover value or change to a weighted interpolation?

I'm not getting any lean knocks (on my stoiciometric tune I would see 3-7 knocks per commute; now seeing 0-2), so I'm not *too* worried about it, but the weather is quite chilly right now (14-30 degrees), and I'm a little concerned about how it will respond to higher loads when the intake temp is 80-100 degrees in the summer.

I appreciate any help you can provide!
Attachments
datalog0000.fpdl
Morning datalog
(4.72 MiB) Downloaded 277 times
8feb14.fpcal
My current calibration
(21.11 KiB) Downloaded 273 times
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Hondata
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Re: High/low load Closed Loop Crossover

Post by Hondata »

By default closed loop to open loop is triggered by throttle position, and some cars have a delay as well. Check 'Use MAP to determine WOT' if you want it switch over sooner.
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bigbadspoon
Posts: 34
Joined: Wed Mar 13, 2013 3:20 pm

Re: High/low load Closed Loop Crossover

Post by bigbadspoon »

Thanks you the quick reply! Sorry if I wasn't more clear. I don't really care if it switches into open loop at 70 kPa, as that's kind of a middle ground. In the closed loop/lambda tables in the calibration window, there's a handful of tables:

Closed loop target lambda: I set to 15.7
Closed loop target lambda limit: I set to 15.7 for temps over 212
Closed loop target lambda low load: I set to 15.7 for 176+
Closed loop target lambda high load: This is set to 14 by default, which I think is fine, *but* at pressures from 50-80 kPa (30-60% throttle), I see ratios more like 15.1-15.4.

So, it's doing something, I think, as it's a tiny bit richer than normal; I'm just not clear on whether it's interpolating or if there's a switch and it goes from one table to the other. If it's better to just set the open loop trigger to be sooner, then I guess I don't fully understand the purpose of this table?
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