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Car is a cammed Ls1 m6. Runs great. Did the tuning. Afrs are right where I like them. Only issue that I can’t get rid of is on instances of decel and then coming to a stop. Car has 42 # injectors. Goes rich on decel. DFCO covers most of it. However decel from 60 to a stop, going down through gears. DFCO cuts off in 2nd usually and then the STFTs go way negative cause it’s trying to lean it out but min pulse width won’t go lower. So by the time I stop and idle at 900rpm thw STFTs are both at -32 and it idles at 18-19AFR until they slowly crawl back up above 0. It’s not in the VE map car runs fine in open loop VE, Open loop MAF and Open loop blended. it’s the STFTs themself and idk how to stop this. I’d thought about the hybrid method but my car idles at 70kpa and I don’t think id have enough resolution to my map table. I.E. chugging up my hill in the morning while the car is still chilly doesn’t give me a big enough difference to compensate with open loop idle. I know the real fix is fixing the rich decel. But I’m unsure how to do this. Not wanting to be spoonfed but I’ve tried and tried to fix this. Can someone point me in the direction?
Try to cut down the Min Fuel milligrams in the Transient tab and work on those off throttle cells in the VE table while tuning in SD. This may help you out or at least lessen the STFT corrections.
Try to cut down the Min Fuel milligrams in the Transient tab and work on those off throttle cells in the VE table while tuning in SD. This may help you out or at least lessen the STFT corrections.
I’ll have to look at my tables again but I’ve long done the min fuel mg and have already tinkered(I think fixed) with my transient fuelings to fix larger on and off throttle leaning and richness and to help with my exit DFCO lean spike. Doesn’t matter how much I take out of the VE table during deep decel though the afrs won’t lean up.
I’d have to take a look at a recent log to verify. but it Seems 1.7 is my bottom pulse width. Can set my AFR commanded to 18-19.0 and decel still won’t lean up, wants to stay around 13.5ish, curse of the 42 pounders maybe?..I’ve hidden it with DFCO but it’s causing me to have this issue. I’ve long drove around it but I’m rather tired of it. I’ve tried a lot of things and idk where else to look. A thought came to mind of setting the idle to 775-800 rpm and doing the PE hack at 800rpm instead of 1200, as I would exit the open loop as soon as I took off. But Car really doesn’t like to idle that low.
Last edited by mstansbury0704; Sep 29, 2021 at 03:23 PM.
Try cutting down your minimum pulse on the injectors. They can only cut to as low as that number is. Anything above 0 throttle won’t be affected. Just hit the idle and decel areas and it should help.
Try cutting down your minimum pulse on the injectors. They can only cut to as low as that number is. Anything above 0 throttle won’t be affected. Just hit the idle and decel areas and it should help.
I BELEIVE that I tried that and they’d still bottom out at 1.7…
You have HPTuners? I’d love for some help on which table I need to mess with in getting my pulsewidths down..I think I’ve tried it already and I think I even messed with my short pulse adder trying to stop it from bottoming out at 1.7. Seems like there is a hidden stop or something that I’m missing and I eventually gave up. It’s annoying enough that I’m almost tempted to go open loop and be done. Right now the car idles around 15.6-15.8 and is super happy there..I just wish we could open loop idle and had an exit tps lol. The only thing that could be brushed up is the very very low maf hz which I tinkered with a little today. In MAF only it was trying to idle around 16.3 but I know that isn’t my problem so I only made one adjustment.
Last edited by mstansbury0704; Sep 30, 2021 at 12:01 AM.
You could post the tune.
I’ve fixed that issue by lowering the min injector pulse and the min fuel milligrams.
What 42 pounders and do you have the correct injector data?
If I read correctly the PE hack works at 1200 rpm. Why not leave it that way?
Big overlap cam would like to be lean as you noted. The NB O2’s are likely confused at idle due to the overlap.
You could post the tune.
I’ve fixed that issue by lowering the min injector pulse and the min fuel milligrams.
What 42 pounders and do you have the correct injector data?
If I read correctly the PE hack works at 1200 rpm. Why not leave it that way?
Big overlap cam would like to be lean as you noted. The NB O2’s are likely confused at idle due to the overlap.
injectors are FIC and inj data is correct.
I don’t know if PE hack would work just because I idle at 70kpa and I don’t see a whole lot of resolution during low tps driving, it’s actually was a major PITA to tune my transients and everything because of it…actually does PE always reference the MAF table even when under the blended cut off rpm? I don’t assume it does but hell I might be wrong
I just don’t know if it would work for me. I can try it. But definitely need to know that intricate detail lol.
All be it im not below 1200 a whole lot but during anytime I am and actually accelerating or say as I’m chugging up my hill or in parking lots or trying to shut my car up when I see a town cop. My car won’t like trying to drive on fueling Meant for it to idle at 15.5.. I thought I tried it and would see 17.0 AFR during any load. Please forgive my memory. This issue has been causing me to go bald for a while. Lol
I will post my tune from today. EDIT: Actually just noticed my min fuel mg is .001.. oop. mustve been one of my hairbrained attempts at fixing it a few months ago and forgot to set it back and never even noticed it... infact i dont even know what that setting really adjusts I just know .015-.02 is what the norm is haha... but yea its a Toon. dont grill me too much...VE is probably all hacked to **** and back from me trying to fix this, once i get my injector pulsewidth to behave i think ill retune my VE below 2krpm.
Last edited by mstansbury0704; Sep 30, 2021 at 01:48 AM.
Set inj min pulse to .395. Still the same. Car is locked up at 1.6-1.7 pulsewidth. Even during 19.0 vcm commanded AFR on decel its stuck at 13.7ish AFR and injector pulsewidth at 1.6 or 1.7.
I have logs. Made some big changes to secondary VE on the decel areas as a test and still no change. Put the old tune back in it. Idk what it’s deal is. This car has dumb quirks that I’ve searched for similar issues but never found.. Such as the ac making it cruise control in general. Fixed that pretty easy with the ac torque settings but still trying to figure out why when I go WOT with AC on or turn the AC off during a drive cycle it idle hangs..Atleast I can cruise around with ac I guess. It’s a T-Top car anyway
Are you actually entering DFCO? Or is your rowing down through the gears resetting the spark decrement each time you downshift, preventing the actual DFCO entry? If you're not actually reaching the (still stock, probably too low...) spark threshold for fuel cut, closed loop doesn't get disabled by DFCO. A log would tell... The problem really is injectors that behave poorly in the nonlinear region...but it does make sense to prevent the issue with DFCO. Let's see data.
I have tuned DFCO to activate again with my elevated map levels. It does exit when I clutch in to downshift say from 4th to 3rd and then re enters upon resumed deceleration. The only thing I can’t get it to do is enter dfco in 1st or 2nd. I assume it’s a slightly lesser load and pulling just enough vacuum to be above the entry threshold I have set, I didn’t care very much at first, but I think I’ve tried to make it enter and it just seems to refuse to enter dfco in low gears If it is in dfco and I pop it quickly into neutral and brake to a stop it idles fine because the stft don’t have enough time to go full sausage negative. And from what I see, closed loop does get disabled by entering DFCO. It shuts everything off including the fuel trimming and resets them to 0 again and pulsewidths drop to like .3 ..on the other hand, if I could get dfco to be active in 2nd gear I likely would forget about this problem because it would stop occurring. I’ve kind of noticed that at lower rpms in decel my car can pull to about a 14.3 which is still rich but it’s not enough to cause issues when stopping. It’s at say 3500 in 2nd gear that the car just can’t get leaner than 13.3-13.5ish and in response quickly goes -32 fuel trims on my scanner
Last edited by mstansbury0704; Oct 4, 2021 at 11:41 AM.
You want to see a log? Or a blowup of my dfco settings?
as I said earlier. My car must have been dropped at birth. It has stupid issues such as turning off the AC while driving making it idle hang or going WOT with the ac on(sometimes) makes it idle hang too. Searching has never found a similar issue. I just chalked this all up to my car being my car. But I’ll post up a log once I get home
the AFR issue is causing me issues with many things during daily driving so I’m at a loss on fixing it
Last edited by mstansbury0704; Oct 4, 2021 at 11:51 AM.
Both logs are from the same day I was messing with inj pulse min. Min pulse 395 is an open loop log where on moments of decel you can see me manually command 19.0 AFR and car is still hung on 13.5ish AFR. It seems around 2-2500 rpm it has the ability to lean out but not at rpms above that even though in both instances the pulsewidth bottom is about 1.7..confusing or possibly an issue of cam overlap. also, helps to note the spec of the car i guess. 235/243|.630/.610| 111+2 LSA. PRC 225s, full exhaust, ls6 intake, MWC 9 inch.
Looks like you are burying error into the MAF and VE tables. Not sure how you are generating the corrections for them, but there is no way you are netting over 1.0g/cyl at 95kpa baro without boost. I would double check that injector data. You did already mention it was correct, but the values in the IFR table suggest it is not.
Looks like you are burying error into the MAF and VE tables. Not sure how you are generating the corrections for them, but there is no way you are netting over 1.0g/cyl at 95kpa baro without boost. I would double check that injector data. You did already mention it was correct, but the values in the IFR table suggest it is not.
and which values do you suggest?
attached are my IFR values and after HPtuners auto correction when entered they are all exactly as sent
EDIT:
is it possible I am nearly out of pump. I.E. under WOT I’m dropping rail pressure slightly and compensating for it by tuning over top of it? AFAIK cyl air mass is based off your VE or MAF scaling.
Last edited by mstansbury0704; Oct 4, 2021 at 09:08 PM.
Yeah, if you can't trust your fuel pressure, you can't calibrate it based on fueling error. That's always a risk. But my concern was more about you saying they are 42lb injectors but the table there saying they are 49. Seems like you have the wrong data?
Yeah, if you can't trust your fuel pressure, you can't calibrate it based on fueling error. That's always a risk. But my concern was more about you saying they are 42lb injectors but the table there saying they are 49. Seems like you have the wrong data?
yes this makes me want to do some digging actually. The file I have attached states whether they are at 3 bar or 4 bar “in the file name” yet my file name states FIC 440CC-42LBBOSCHLS1SCALED…now I’m at a conundrum. You may be onto something. They may have sent me a wrong inj data sheet. That means I’ll have to retune the entire thing eh? LOL
EDIT: Im pretty sure these are Bosch 0280155868 Which are infact 42lb at 58 PSI, but idfk how they get their data of 49...when taking the bosch rated 36 at 43.5 and multiplying by the 1.1547 you get 41.56...Is this a case where my ENTIRE set of values is wrong, such as my short pulse and my offset, or I can just update my flow rate vs kpa data?...Im pretty pissed off...I dont even know how to rescale this data at this point because i dont understand how they get their base rate of 49... Im so mad i didnt notice it was off. Teach me for trusting a vendor..
Edit#2
attached is NEW data. Ive updated everything along with min fuel mg and FTW impact. These base IFR values are nearly 20% less than what i had currently, how does this effect my VE table? Im grinding gears wrapping my brain around if i should add 10% of fuel or remove 10% for my initial logging. My startup airflow tables shouldnt be severely effected correct?? Im hoping i can just slap this new data in, retune VE, and MAF and be okay...heres to being hopeful
Last edited by mstansbury0704; Oct 4, 2021 at 11:31 PM.
This is what FIC just sent me when I asked them again for the injector data. The data I just updated I stole from hptuners forum. The real question is now, which is right?
Attached is tune with FIC injector data.
Last edited by mstansbury0704; Oct 5, 2021 at 08:47 AM.
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Idle issues caused by STFT 
