There are a few things that can be adjusted. Save it for when VE is correct. No use in tuning around a rich idle.
There are a few things that can be adjusted. Save it for when VE is correct. No use in tuning around a rich idle.
Thanks Man. Will try to get the VE tuning first, next will be MAF and put the tune back in Closed Loop. Then will go from there.Originally Posted by SiriusC1024
@SiriusC1024
Finished with the VE & MAF tuning to the best of my knowledge. Put the tune back in closed loop and did some logging today. My observations during the short drive are as following:
1) I can feel some hesitation while driving at a steady speed on the highway.
2) The same issue I am having sometimes with idle falling below desired idle noticeably to the extent it wants to die and picks up back to idle desired while down shifting and slowing down to make a turn at a very slow speed.
I have attached the tune and the log hoping to get some feedback into what needs to be adjusted to sort out the above issues.
VE looks like it could use some more work. Mind posting an SD tune and log? Don't forget to go into VCM Scanner to clear LTFT's before logging. I see a few other things, but once that's set right it'll make adjustments easier.
Thanks for the reply. Will share the SD tune and log later on today. I normally keep the LTFTs disabled and clear the trims from the scanner.
Go ahead and enable the LTFT's since it should be close. It's good to see both.
Here is the log and VE tune done with both LTFTs & STFTs disabled. This is based on Videos from Chopperdoc181 in youtube.
Based on the files, hope some specific changes could be advised to address the hesitation and idle drop issues mentioned earlier.
No no. I said both ENABLED lol.
Describe the hesitation. Is it off-idle, decel, steady cruising?
Here. I've made some changes. Log this, please. Let me know how it does.
Thanks man. Noticed you have made lots of changes into the tune.
I noticed the hesitation at steady cruise, but honestly did not pay attention in off-idle or decel. might be there, or might not but definitely at steady cruise.
just have a few clarifications.
1)I advanced the timing at idle and lower in all spark tables, but noticed you lowered them in the revised tune. Is not this going to cause idle dip?
2) In my closed loop tune, I changed the EQ ratio (gas) under power enrichment, but in the SD tune it is different. Is it OK to make the EQ(gas) in the SD tune the same as what is in the closed loop tune?
3) I am going to flash the new tune-SD you made and go for a drive. The values I get in the AFR error histogram will be copied and special pasted by % half into the VE table, correct?
Thanks in advance.
1 - This is done to make a smoother transition between idle and base spark. If idle spark is high it makes underspeed corrections less effective.
2 - I adjusted the OL EQ ratio not PE. Can't have 1.0 for all temperatures.
3 - Yes. I'd still like to see a log.
Everyday I am learning something new. Thanks.
Will share the log once done.
My question was about the PE. Just please have a look at the file I shared earlier when the MAF was enabled and the one in SD. This is what I was referring to. Which one should I keep?
Ah I see. Go ahead and keep the settings like they are now. You can adjust that ancillary fine-tuning stuff later.
Will do that. Thanks
Went for a 20 min drive and here is the log. I did not change anything into the tune you modified. That is why I did not attach it again in this post. Maybe based on this log, some more changes you could make into tune please.
I noticed that the hesitation I was having during steady cruise has gone or at least did not feel it like before. However, the bucking issue I was having earlier is still the same.
One thing I've had before is that combining injection timing adjustments with incorrect injector data can increase bucking and feel like a slight miss/hesitation during cruise. I've touched up VE and set injection timing to stock. This thread started about which set of data is correct. Haven't had any problems out of the converted data. VE looks a little off from what it should be despite the trims saying it's accurate. Let's see what happens.
There are idle issues. Log STIT on the next.
Thanks for your time man.
Did another log with the new tune. I have noticed less bucking or I would say it has improved. I am also wondering if it is normal that the car wants to surge or die when the IAT goes high like above 100 Deg F especially when being it traffic? Shall I log under high IAT as well or you will be able to capture it in the tune?
Thanks in advance
For the high IAT problem in traffic I'd have to see it. Could be related to higher BRAF than needed, for which I compensated.
I'm assuming your bucking problem happens around 1500rpm and 40mph? Do you have a lightweight flywheel? I've lowered spark on the low end to smooth things out. Brought it up on the high end to sustain torque with rpm.
See what you think. Let me know any details. Log any problem spots and point them out specifically.
Perform a throttle relearn. Pedal is showing 0.4% at idle.
Thanks man.
I am going to log with the updated Tune.
The bucking is at a low rpm as you mentioned but I am did not pay attention to the exact speed. could be at 40 rpm or even less.
I have LS7 clutch with OEM flywheel on my LS6 engine. However, not sure if it is LS2 or LS7 flywheel as it was installed by the previous owner.
As far as the throttle position, I have done throttle relean several times. Sometimes it shows 0% and sometimes 0.4%. This is with new OEM throttle position sensor. I am going to perform relean again before logging.
The stupid fuel pump failed. The new pump did not last long. Unfortunately, logging will not be soon.
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