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See if the TPS Value when lightly cruising is under the value for the idle lockout, could be going in and out of closed loop idle from there. Either that or VEAL is pulling too much fuel and its going real lean in the cruise cells, if its consistently lean and jerky
See if the TPS Value when lightly cruising is under the value for the idle lockout, could be going in and out of closed loop idle from there. Either that or VEAL is pulling too much fuel and its going real lean in the cruise cells, if its consistently lean and jerky
Thanks, I'll give it a look tomorrow! Its consistently jerky, but the lean condition is more inconsistent when compared to the jerky behavior of the car.
Hey, sorry for not responding after such a long time! So, I have been playing around with my tune, and today I just tried to take the car out for a drive for some auto-tuning using VEAL, and it went...poorly. The first thing I noticed is when off throttle, in gear and coasting, my AFRs for some reason will shoot up to 22.4 and sit there...I have no idea why. The other thing is after off throttle and in gear coasting, when I press the gas again, my car literally jerks back and forth like it is trying to stabilize. This also sometimes happens when coasting in gear, or just jabbing the throttle while cruising. My AFRs are also still going lean when starting from a stop. Honestly...I have no idea where to start from here. I took two logs and I will attach my current tune. One of the logs also shows the behavior where the RPM hangs around 2500 RPM during a light blip of the throttle when the engine is still under 160 degrees F and warming up. No idea what that is about. The other log is from when I was auto tuning; you can see the AFRs go to 22.4 while coasting from 37.645 seconds to 39.448 seconds, and also from 66.444 seconds to 71.583 seconds. As for the jerkiness when giving it throttle, I am not sure at all what may be causing that. When revving the car at a standstill, everything seems fine (although it does go a bit lean at first). Its when the engine is under the load of the vehicle moving where things start to go very bad. Thanks for any help! I'm not sure at all what is going on, so any help is greatly appreciated. The main two things I was playing around with were decel fuel cut and accel enrich.
The car goes lean when you give it 0 throttle as over-run fuel cut is on as the car isn't injecting any fuel, this is normal and not an issue. The jerkiness when exiting over-run fuel cut is just normal fuel tune things, so VE Table and your acceleration enrichment settings. My AE barely adds any fuel on throttle (think its like max 12% extra) and my car is fine with it, this may not be the case for your car. My car is still a little bit jerky when over-run fuel cut comes on, however my transition out of it is smooth. Should get better the more you tune your fuel.
Turn off progressive fuel return in overrun fuel cut. You can use progressive cut, but progressive fuel return gives those kicks.
EGO correction is causing some pretty high frequency oscillations, and AE is dumping way too much fuel. You can see it setting off way too often in your log, making injector pulsewidth look like a sawtooth more often than not.
You should be able to turn AE off entirely and drive around with a very very light foot to make sure the VE table is right. From there you can add more in to get the throttle response back. I prefer doing it that way because it's possible to add way too much fuel way too quickly otherwise and it will confuse autotune.
The car goes lean when you give it 0 throttle as over-run fuel cut is on as the car isn't injecting any fuel, this is normal and not an issue. The jerkiness when exiting over-run fuel cut is just normal fuel tune things, so VE Table and your acceleration enrichment settings. My AE barely adds any fuel on throttle (think its like max 12% extra) and my car is fine with it, this may not be the case for your car. My car is still a little bit jerky when over-run fuel cut comes on, however my transition out of it is smooth. Should get better the more you tune your fuel.
Gotcha, thanks! So me seeing that 22.4 AFR shouldn't be an issue? It was just alarming to see that and I thought it was kind of weird. Would you mind sharing your AE table so I can get a comparison of it to mine? I have a feeling mine is adding a lot of fuel compared to yours based on your 12% number.
Originally Posted by deezums
Turn off progressive fuel return in overrun fuel cut. You can use progressive cut, but progressive fuel return gives those kicks.
EGO correction is causing some pretty high frequency oscillations, and AE is dumping way too much fuel. You can see it setting off way too often in your log, making injector pulsewidth look like a sawtooth more often than not.
You should be able to turn AE off entirely and drive around with a very very light foot to make sure the VE table is right. From there you can add more in to get the throttle response back. I prefer doing it that way because it's possible to add way too much fuel way too quickly otherwise and it will confuse autotune.
Thanks! I will turn off progressive fuel return. I'll have to look into my EGO correction settings. To turn AE off entirely I'm guessing I just 0 out the table? I don't see a way to just turn it off besides the EAE or XTAU settings, which I currently have off.
Yeah just zero the table out if you want to disable it entirely. Its basically tuned by feel, the AFR change from AE is insignificant and as long as the car revs freely and doesn't stumble with quick throttle jabs at multiple RPMs/loads then your settings are fine. Using Accel Pump AE. My max is actually 8% and my car seems to like that. I have -10% at negative TPSDot so releasing the throttle quickly pulls 10% fuel, car is fine with it. Can change to 0 if your car doesn't like it.
My AFR Gauge actually goes full - - - - whenever my fuel cut kicks on, yours may just go the max lean value it can show. Not harmful as there is no load on the engine when at no throttle coasting in gear.
Yeah just zero the table out if you want to disable it entirely. Its basically tuned by feel, the AFR change from AE is insignificant and as long as the car revs freely and doesn't stumble with quick throttle jabs at multiple RPMs/loads then your settings are fine. Using Accel Pump AE. My max is actually 8% and my car seems to like that. I have -10% at negative TPSDot so releasing the throttle quickly pulls 10% fuel, car is fine with it. Can change to 0 if your car doesn't like it.
My AFR Gauge actually goes full - - - - whenever my fuel cut kicks on, yours may just go the max lean value it can show. Not harmful as there is no load on the engine when at no throttle coasting in gear.
Ahh I see, thank you! Good to know that is normal during fuel cut. This is my first time doing anything like this, so I appreciate the information and clarification. I will play with my AE again after doing some more VEAL tuning and see how it goes as well.
For the idle hang lower the dash pot adder to 2 it is in the closed loop idle settings. You may have to lower the initial values as well. I would make the range less steep across the rows. People that don't understand the engines requirement from the AE usually have weird tunes with too much timing at idle and/or off idle to improve throttle response.
For the idle hang lower the dash pot adder to 2 it is in the closed loop idle settings. You may have to lower the initial values as well. I would make the range less steep across the rows. People that don't understand the engines requirement from the AE usually have weird tunes with too much timing at idle and/or off idle to improve throttle response.
Thanks, I'll look into editing those settings in my tune and see how it goes in regards to the idle hang. I'm not sure if firmware revision 1.5.1 has a dash pot adder field, since I don't remember seeing it. I can look again, but last I remember I didn't see anything for that setting.
Been trying a few different things to get my tune close to smooth. Changing the dash pot adder percentage didn't seem to help the rev hang, so I will have to take a look at the initial values still. I tried to figure out why my AFRs in my logs were oscillating so much, so as a test I turned off EGO correction and ran VEAL while taking a datalog. When looking at the log, my AFRs are much more smooth compared to with EGO correction on. Of course, from my understanding, it is good to have EGO correction on, so any tips on how I can adjust my EGO correction settings to maybe smooth out those oscillations? I noticed with EGO correction off, my AFRs shot up to around 15.3 to 15.6 at idle when the cooling fan kicked on.
When rolling on the throttle smooth coming out of decel fuel cut, the car seems to be fine, but when stabbing the throttle, it kind of jerks around a bit. I'm guessing this is normal due to the sudden increase in throttle position? I still have to adjust my AE table, so that is something I will have to look into as well.
Other than that, I still have to do a bit more driving and VEAL tuning to really see how the car behaves over time, so that is something I will be doing throughout the week. Next step after getting a decent tune down is to install the larger injectors and make the right injector adjustments. I attached my tune and a data log from today if anyone is interested in taking a look. Thank you!
EGO Correction oscillations are PID related, requires some work/looking at logs to get correct. How sensitive the algo is depends on your firmware version, if you are running 1.5.1 there was an EGO correction pid issue that is fixed in later firmware revisions.
The attached log has EGO Correction at 100% the entire log, so you may have already done this?
Its possible your AE is adding too much fuel causing a stumble at throttle tip in, I would suggest turning it down a bunch (max AE being like 15% instead of 60%) and seeing how it works.
With a naturally aspirated car you can run without EGO Correction on while you fix up the fuel and AE issues, before you have time to tune the PID values. It shouldn't ever get lean enough to hurt anything
EGO Correction oscillations are PID related, requires some work/looking at logs to get correct. How sensitive the algo is depends on your firmware version, if you are running 1.5.1 there was an EGO correction pid issue that is fixed in later firmware revisions.
The attached log has EGO Correction at 100% the entire log, so you may have already done this?
Its possible your AE is adding too much fuel causing a stumble at throttle tip in, I would suggest turning it down a bunch (max AE being like 15% instead of 60%) and seeing how it works.
With a naturally aspirated car you can run without EGO Correction on while you fix up the fuel and AE issues, before you have time to tune the PID values. It shouldn't ever get lean enough to hurt anything
Interesting, I'm currently on firmware 1.5.1. With that log, I had EGO correction off...would that make it show as 100% in the log? I didn't realize that until you mentioned it, but yes it was turned off. I will tune my AE down, I didn't get the chance to play with that today, but I will mess with it tomorrow! I was always told its recommended to use "Simple" for EGO correction, so I didn't touch the PID values. I will look into what I can do to tune the PID values in EGO correction though!
How good would you say VEAL is at tuning the fuel table? It seems to be doing a pretty decent job right now, but there are definitely spots where I'm a bit confused on why VEAL is doing what its doing.
VEAL is awesome at tuning the fuel table as long as your AFR Gauge matches the gauge inside of tuner studio at various RPMs and engine loads. It will tune based off of your AFR Target table, there is a weird part of yours at 1500 rpm where its 14.5 instead of 14.7, maybe change that to 14.7 so its uniform across the target table. Start at normal then ramp it up to hard, then very hard as all the parts of your table start matching. Lock it out so it doesn't take values under 35 kPA or under 1500RPM and you should be good.
EGO of 100% means it isn't making any corrections to fueling. I haven't used simple but my basemap came with decent PID values I haven't touched, but my 1.4.0 firmware is way less sensitive so my numbers won't work the same on your setup. As you are on 1.5.1 I would recommend looking into upgrading your firmware, not certain of the exact EGO issue but its pretty noticable.
Engine state settings look untouched.
Injector voltage correction is turned off. Why?
And u have used Simple EGO algorhithm - good for a narrow band o2 sensors.
for wideband sensors PID algorithm is much better suited .
VEAL is awesome at tuning the fuel table as long as your AFR Gauge matches the gauge inside of tuner studio at various RPMs and engine loads. It will tune based off of your AFR Target table, there is a weird part of yours at 1500 rpm where its 14.5 instead of 14.7, maybe change that to 14.7 so its uniform across the target table. Start at normal then ramp it up to hard, then very hard as all the parts of your table start matching. Lock it out so it doesn't take values under 35 kPA or under 1500RPM and you should be good.
EGO of 100% means it isn't making any corrections to fueling. I haven't used simple but my basemap came with decent PID values I haven't touched, but my 1.4.0 firmware is way less sensitive so my numbers won't work the same on your setup. As you are on 1.5.1 I would recommend looking into upgrading your firmware, not certain of the exact EGO issue but its pretty noticable.
Thanks! I will look into those settings. I will try upgrading the firmware as well, hopefully that will help with the EGO issue like you said. I'll have to take a look at some PID values for EGO and then start tuning mine to see where I can get it to act pretty normal.
Originally Posted by irodd
Engine state settings look untouched.
Injector voltage correction is turned off. Why?
And u have used Simple EGO algorhithm - good for a narrow band o2 sensors.
for wideband sensors PID algorithm is much better suited .
I honestly didn't touch the injector voltage correction because I didn't know it was there. I am going off of the basemap I got with my MSPNP, so there are some settings that I haven't touched due to lack of research and knowledge of what they are or what they do. I was using the simple EGO algorithm based on recommendations from an Evans Tuning performance Academy training course I purchased (I plan on taking my car to him for tuning after turbo), but I can change to PID and play around with that, thanks!
Simple EGO Algorithm - This method of closed-loop EGO control is well-suited to use with a narrowband O2 sensor.
PID EGO Algorithm - This method incorporates a Proportional Integral Derivative control loop which tuned properly, adjusts the amount of fuel being injected to quickly get to the target, and then maintains the target without any oscillation.
Simple EGO Algorithm - This method of closed-loop EGO control is well-suited to use with a narrowband O2 sensor.
PID EGO Algorithm - This method incorporates a Proportional Integral Derivative control loop which tuned properly, adjusts the amount of fuel being injected to quickly get to the target, and then maintains the target without any oscillation.
Thanks, I'll give PID EGO some more adjustments in my tune. I am currently trying to get it tuned right, but I keep getting oscillations. Definitely need to research more on how to tune that because I don't know much at all about PID.
PedXing has good videos on this as well, pinned at the top of this forum section.
Thank you! I will try tuning the I value first and go from there. I'll check out the PedXing video as well. Going to try a few things tomorrow and Friday, and then report back on my results.
10-22-2020, 09:09 PM
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Thank you!
