Yeah, but the problem is it's a change that's not reported in the injector pulsewidth...
Printable View
I hadn't looked at it that way yet. That is quite strange then
I know gen 4's don't report inj PW the same as gen 3's
correct, injector PW is the same. you would think it would be doubled
Actually, my previous post was dumb.
Of course the injector Pw is the same. Why wouldn't it be? The fueling requirements haven't changed. The only problem is the base fueling the computer is coming up with is wrong for whatever reason, then fuel trims are helping it correct back to lambda = 1. Injector PW SHOULD be the same.
Injector pulse width in Gen 4 I believe are predicted not "actual" but that being said I've also noticed a strange phenomenon if you let the car idle for about 15 minutes, once IAT goes from 30* to about 40*C on mine the engine revs up about 200rpm and the trims go -15 for a bit, no change in fuel trim cell no change in command air fuel just goes -15 for no reason at all, then settles back down after about 45 seconds.
With all these weird phenomenons going on you almost wish you had a 411 ECU because there is clearly tables/options in there that we still don't know about. And it's not purge btw that's disconnected.
That's really really strange....
I'll try this a few more times but what's also strange is try "downloading' the full flash then edit it and reupload it back to the engine seems like the rich after flash issue is not there when you do it this way, I've tried on two separate occasions and both times trims started at 0 and did not sway but it could have been just a freak two times I'll report back this week.
That's odd...I've never noticed that, but I always upload the cal only...I rarely ever read a vehicle more than once. Usually only if I messed up file names and saved more than 1 revision of a tune, and I'm not sure which one is currently in there when I was logging LOL.
I do believe it's mostly solved... I've run this a few times back to back, and things are consistent.. whoever said they thought it was linked to IVT... they were right... but it's only linked the first time after flash or battery power reset..
http://www.hptuners.com/forum/showth...U-really/page2
"ok... I think it's solved... I put all fuel injector settings to either 0 or 1... reflashed, settings on the simulator were setup like this for consistency.. 1021rpm, 46mpa MAP, 223f coolant, 99f IAT. then:
1) instantly the HPTuners injector pulse and scope pulse were much closer together then earlier tests, however at first the scope was showing longer pulse as expected. HPT = 5.11ms vs scope of 5.45ms, IVT was ~235f and increasing...
2) Once IVT reached max temp (333.1F) then the scope injector pulse finally matched the HPTuners Injector pulse... this time was ~8min. 5.12ms for HPT, and 5.13ms on scope, with IVT at 333.1f,
3) IF engine RPM is stopped, or KEY is turned OFF for just a min, IVT decreases back to coolant temp within a few minutes, however if restarted, pulse width still match, even though IVT iis cold (near coolant temp of ~225f) it continues climbing back to ~333f. Scope pulse does not change this time. It stays "lean" and matches the HPTuners PW.
4) IF complete battery power is removed, OR it is FLASHED, then the scope Injector PW resets and the process starts over (the process = scope actual PW is higher than HPTuners reported PW until the IVT gets high for the first time, even when coolant is hot and engine is started hot).
So, someone also said they go WOT once or twice then it seems to be fixed right after flashing, I think that's because it heats up the intake valve much faster than idling/low load.
"
Realtime video of this event...
at 4:57 pulse are equal, RPM stopped/key off. IVT allowed to cool for ~3min.
at 7:46 started back up, first at 600rpm then back to normal 1025rpm. Pulse match perfectly. If I power down batt or reflash, then this pattern resets.
https://youtu.be/H317c68o1g8
------------------------------------------------------------------------------------------------------------------------------------------------------------
ADDED DATA FROM THE OTHER POST (bench simulator)... http://www.hptuners.com/forum/showth...U-really/page3
"At 72F coolant temp... Scope Injector Pulse did not change, however either did Inj. Tip Temp... it stayed at 72.1. On the last test at 0F coolant, Inj. Tip pegged at 926F, but it also stayed there and Scope Pulse width did not change.
151F coolant temps... Injector Scope PW is not changing and Inj Tip and IVT started at 151F... ITTis down to 112.7F and IVT at 281F... no change.
162F shows just a hint of increased scope PW which tapers off pretty quick... and if I instantly go to 195F coolant temps after it tapers off to normal, then PW doesn't increase... it stays true to what HPTuners reports.
178F does seem to startoff with increased Scope Inj. Pulse Width.. but not as much increase as hotter temps. Strange. 151F doesnt show any increase.
~195F coolant temps... shows the typical injector pulse offsets that go away as IVT's taper off over 303F.. (when started from ~195F).
~232F coolant temps.. similar times as 195F, however 340F IVT temps and 149F Inj Tip Temps when Scope Inj. Pulse stabilizes and equals HPTuners.
~268F coolant temps.. similar to the "HOT" temps (195-232F) except scope PW didnt taper off and match HPTuners until IVT = 359.15 and is now completely steady... while ITT keeps falling slowly around 152.6, now 149.4 after ~30s... 20s later 149.2, etc.
So, if you flash hot, or Batt disconnect hot, then immediately restart, you will see rich conditions right away.. if you let the engine cool down to ~151F coolant temps then start, you shouldn't see it right away, as coolant temp is low, and the IVT starts heating up and drives down the hidden PW adder... IVT and coolant temp increase pretty fast, so the effect may be minimal.
So there you have it... something is happening that starts at ~151F and below 162F coolant temp that is creating the increased scope PulseWidth after flash or batt disconnect and continues to increase scope PW up to at least 268F coolant temps. Maybe with that description HPTuners can find something? I did this with the old LT1 Tunercats... described what I was seeing with Baro Reset... and they found a new parameter to add.."
What settings did you set to 0 or 1? If you set the offset/short pulse adder tables to 0 then we agree...
"Reported" + short pulse adder + offset = actual electrical PW
With short pulse adder & offset being 0, all that is left is reported = actual electrical PW, which would match up with what I saw when I put the 'scope on mine.
Think this was the general consensus... Glad you were able to prove it. BUT, I also think other unforeseen and back calculated variables may also play a role such as injector temp gains ;) Not sure if you can datalog that one or not? Lots of things in the background of tunes that we are not allowed to see, I've come to find out over the years that's caused more than one headache along the way :) AND as previously stated, other manufacturers vehicles do this same reverse calculated learning event, but atleast their fuel trims will sorta stay near 0 until they meet "their" parameters... Just incase anyone out there is tuning other product lines.
I looked at it just now... hard to say what one is responsible for sure, but the injector drift tends to stop drifting once IVT stops drifting.. Injector Tip continues to fall for many mins after IVT stops climbing but the scope injector drift seems to stop also... but then again injector tip temp stays cool allot longer after RPM is stopped... so who knows.. but still, watch for IVT's to stop moving after a flash or batt disconnect (when restarting hot) and you should be good to go.
My original post... I still like to go through my own "ritual" with this. Wait 15 minutes then run through the gears under load a little, then go back to idle and wait a couple more seconds to a minute then start datalogging. Peace of mind if you will because even waiting for the IVT to settle has still bitten me a time or two.
Great post but hey I was the one that asked to find the BARO for LT1's ;) I noticed after WOT BARO was off so emailed TunerCat and they found BARO update table. They also found a similar BARO update table for E38 for me but in the E38 baro update doesn't seem to affect fueling but I still set it to update at infinity. That's really helpful and yes no wonder this all makes sense when I upload a file and let her sit for 10 minutes I don't see this, most likely because engine cools down.
If you need me to find my original emails about the LT1 Baro reset... I will.. but this post should suffice.. I am dookie454 on camaroz28.com
http://www.camaroz28.com/forums/comp...uction-560089/
been testing and the issue doesn't seem to happen when running in open loop only
did you guys try the switch under fuel/open&closed loop far left
Misc
High DI Enrich
i tried it, i think it reduces the enrichment after the flash
I don't have that option but most of those affect the Command A/F this condition does not affect it just affects fueling after start.
My Rich after start happens just like posted now that I've tested only happens after about 150F open or closed loop.