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Discussion Starter #1
I set the low slope on the injectors and the car is perfect at idle, but when I am driving and the car seems to be running closer to 13.8-14.0 on the widebands. Is this a low slope adjustment that needs to be made?
What is the typical fix for this? PI correction shows fuel being pulled and that does not add up with the gauge readings.
 

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Discussion Starter #3
So when I am driving I have the laptop showing my variable list along with the 2 little Closed Loop PI correction gauges.
It looks to be correcting roughly 10% as the PI gauges show roughly 0.9 with some swing. At idle it is damn near close to 1.0 as expected.

My understanding was that the PI correction would show 0.9, but the wideband would show 14.7 as the correction was being used to get back to stoichiometric. I don't understand why a correction is being made, but I am still showing 13.8 on the AFR.

Should I recalibrate the sensors?
Add fuel somewhere?
Vehicle has an auto with overdrive, but I wouldn't think that would play a part here.
 

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You're correct that the system is pulling about 10% fuel based on the PI correction gauges.

Showing 13.8 on the gauges may be correct. Outside of straight idle, the commanded a/f ratio is never 14.7. Under Fuel > Open Loop, look at the Base Lambda table. You'll see that aside from the very top left (the idle area), commanded lambda is never 1 (14.7). Most places in the table that correspond with normal driving conditions have values like 0.96. That's a commanded a/f of 14.1. On top of that, there are lambda multipliers for both air charge temp and engine coolant temp. Basically, if either of those is on the cool side, the mixture is enriched even more. You can't assume a/f is supposed to be anything. You need to know exactly what's being commanded. (That is a major reason why I prefer to use PI Corrections in closed loop to set up injector low slope rather than running in open loop and trying to get the gauges to read 14.7... you don't 100% know 14.7 is what's commanded even at idle.)

What you should do is go under Variables > Fuel > Open Loop and bring up Desired Lambda. This is the actual, final value being commanded at any given time. Closed loop feedback is cutting 10% fuel in the attempt to achieve this value, not 14.7. If you see a Desired Lambda of 0.94, then seeing 13.8 on the a/f gauges is spot on.
 

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I want to add to this. It's very important to have configured your Innovate controllers' Output properly. If you don't do that, there will be a discrepancy between what the gauges read and what the Pro M thinks a/f is.
 

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DRIVE it for a long time before looking at corrections

Staring at wb readings that are always going to be changing is going to ruin tuning for you

It’s normal for them to change all the time

I can view my wife’s 17 GT a/f gauge, and they are always changing during non WOT conditions
 

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I like the variables list for certain things but I don't like it for monitoring this because it bounces around too much. I was playing with the datalogging initially after I got everything running good and noticed I was very lean at WOT, see attached. It was very clear in Excel format and I had unknowingly changed the inj_compensation to enabled, which I believe Chris said was only used with the fuel pressure sensor feature. I corrected it then logged and compared load to lambda in the open loop fuel table John mentioned and it was right on. Maybe John can chime in because I haven't used it but you can also pull up the fuel table and check the Current Op Point box at the top while driving at a constant load and see where you're at. My mind stiff thinks in AFR but I changed my gauges to lambda so I could compare it to the actual in the software.
 

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Maybe John can chime in because I haven't used it but you can also pull up the fuel table and check the Current Op Point box at the top while driving at a constant load and see where you're at. My mind stiff thinks in AFR but I changed my gauges to lambda so I could compare it to the actual in the software.
Yes... but keep in mind that the fuel table gets further manipulated by tweaks made for ECT and ACT. Just because the fuel table op point says .90 doesn't necessarily mean final commanded lambda is .90. Probably close, but not a given.

Also, you don't show desired (commanded) lambda in that datalog, but my guess is you were rich, not lean. You need to compare commanded to actual to determine lean vs rich.
 

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Yes... but keep in mind that the fuel table gets further manipulated by tweaks made for ECT and ACT. Just because the fuel table op point says .90 doesn't necessarily mean final commanded lambda is .90. Probably close, but not a given.
His ACT and ECT temps are low enough where very little timing will be pulled. At the dyno, I believe people should zero out these two tables. :grin2:

Also, you don't show desired (commanded) lambda in that datalog, but my guess is you were rich, not lean. You need to compare commanded to actual to determine lean vs rich.
Agreed, and it may be time to post a list of variables people should be looking at when at the dyno.

See ya
Michael Plummer
 

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His ACT and ECT temps are low enough where very little timing will be pulled. At the dyno, I believe people should zero out these two tables. :grin2:
I'm talking about fuel enrichment from ECT and ACT, not spark retard. Colder ACTs and ECTs add fuel on top of the base table. If the car is up to temp than ECT usually isn't a factor, but ACT can be, especially this time of year.
 

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Agreed, and it may be time to post a list of variables people should be looking at when at the dyno.

I typically log RPM, Load, Spark Advance, Commanded Lambda (both banks), Actual Lambda (both banks), Fuel PI Corrections (both banks), ACT, ECT, MAF Voltage, Boost, and TP Voltage. I include TP voltage so it's easy to see where I go WOT and where I stop.
 

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I'm talking about fuel enrichment from ECT and ACT, not spark retard. Colder ACTs and ECTs add fuel on top of the base table. If the car is up to temp than ECT usually isn't a factor, but ACT can be, especially this time of year.
Oops, I didn't read the whole thread and I assume everyone is always talking about WOT.
 

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I typically log RPM, Load, Spark Advance, Commanded Lambda (both banks), Actual Lambda (both banks), Fuel PI Corrections (both banks), ACT, ECT, MAF Voltage, Boost, and TP Voltage. I include TP voltage so it's easy to see where I go WOT and where I stop.
Agreed and I also log PCM power, closed-loop status (not needed if you wait for your PI correction needles to move) and EPOS_Synch_Level.

I hope this helps
Michael Plummer
 

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Good point Michael and thanks for the variables. What does the MAF voltage tell you if you know load and TPS voltage for WOT? Also, I know the years may be different (94 here) but my TPS maxes out at 4.6533 volts. Chris told me to leave it alone, more curious what others max out at.
 

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I personally log MAF voltage for a couple reasons. First, I want to make sure I don't peg the meter. I'll grant you you really only need to do that once to know you're not hitting 5V, but I'm always trying to make more and more power, so the voltage keeps creeping up higher. I don't remember exactly, but I think I'm around 4.85V now. Second, if something were to go wrong, the MAF voltage can be a nice diagnostic tool. I've seen cars where the MAF meter was positioned horribly and you can see the air turbulence in the MAF voltage reading.

My TP voltage maxes out similarly to yours. It's fine.
 

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That makes perfect sense. I've got the 92 and I think it's way over sized for my application but now I'm curious, I'll add it to the list. Thanks John.
 
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