Question about closeloop.....
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Question about closeloop.....
Just wondering if anyone has good tips to get closeloop to work \"smooth\". I have closeloop enabled till 730 mbar, but in between 1100-1800 rpm, the car feels like it jerks slightly back and forth, very minimal. When looking at the datalog, the jerking is felt when the car goes from rich to lean(because of closeloop), and it happens around 200-300 mbar. It's not that bad, but it could be better. And also, close loop doesn't seem to be steady. I'm back and forth from 12-17 afr, it seems like it never stays close to 14.7 at all. Any ideas? Thanks............
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Would o2 fuel trim be in any way related to injector offset? The reason I ask is because when I started my calibration, I used a p28 rom, and I had to add +20 on the injector offset section to get idle good. Yesterday, I changed o2 trim from -15 to -20 and the car is acting better than before. So there's a +20 injector offset and a -20 o2 fuel trim, is this just a coincidence????? Thanks
Same question here. O2 fuel trim, Closeloop correction trim, min & max closeloop adjustment... I fail to see the big picture on how these numbers affect closeloop opperation... min/max adjustment are obvious, but how do the other trim settings actually affect these.thething96 wrote:not to sound dumb, but how exactly does the o2 fuel trim work(as far as how closeloop adjusts afr's)????????????? thanks........
- JaredKaragen
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Look I will spell it out for you; though it is simple. The oem mapping is tuned lean; using closeloop to send rich signals, using the o2 sensor as feedback. If the ecu adds x among and switch to rich takes y time, x = some formula of x and y... And repeat. That's the basics. When you disable the o2 on a stock ecu rom: what happens? It runs lean. There's your 15-20% difference, and after tuning you've added about 10-15% to all lower load areas, the oem mapping needed more base 'overshoot' to do it's work. The oem way of lean vacuum mapping saves a lot of emissions when lifting off the throttle; and thus the reason it is that way. Remember, a percentage is normally based off of an oem or 'root' value, and you are certain it is an original value if it has no user definition for a base value. Thus you must think to account for what is different from the stock configuration.
95 Sol Si : D16z6 : TD04H-13C 74 Civic 1200 : 100% Stock
Just to make sure I interpret this correctly: o2 fuel trim, trims the map for OEM style (lean to rich) closeloop opperation. (only applies when closeloop is active?). Now, my other question remains, what does closeloop correction trim (under closeloop settings menu)do? Isn't the o2 fuel trim a closeloop correction trim?... ectune should have a lot more popup boxes that actually explain what certain options are for because some are just to confusing... Love the software, but the helpfile isn't helpful at all, nor is the wiki...
- JaredKaragen
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Oi; I'll say it one more time. The oem mapping is very lean using closeloop to send rich spikes. Since we tune the map different (to stoich) the ecu will pig-rich the motor in closeloop. Trimming back the value closeloop uses fixes the 'overshoot'. Sounds like you are grasping it. This is something that is learned from researching FI computer systems, and books on EFI tuning... The software isn't there to teach you to tune; just enable the ability to tune. The only thing you need to have explained in the app are things that take prescience to how the app works (table reading, datalog settings, etc), and also min/max/nominal defaults. I would expect the app to cost a lot more if it tought you how to tune.
95 Sol Si : D16z6 : TD04H-13C 74 Civic 1200 : 100% Stock
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