WOT tuning 6.1 5spt auto, 9psi boost...something pulling timing?

[ngc1068]

yes

Haha, okay, I guess I?m getting warmer? Do you think that value could be causing my issue? Would you mind advising on how I should go about adjusting it? Sorry to be a nag, I?ve worn out google and the forum advanced search and keep getting nothing helpful. I do sincerely appreciate the help!

[ngc1068]

Well raised max engine torque in TCM up to 3000, no change in behavior. It is for certain this only happens in 2nd gear WOT pull... seems to occur right at 3500rpm every time....I kind of feel that all but rules out hardware (wiring, injectors, plugs, coils, etc).

[LilSick]

post the tune and a fresh log ?

[ngc1068]

Hi, Here is a fresh log, first pull is 2nd gear, aborted due to stumbling, second pull is in 3rd gear, no problem.
23-05-19 18-47-02.hpl

I swear it feels sounds like its running up against a rev limiter... as crazy as that sounds.

Fresh copy of calibration file:
2009 6.1 Challenger Auto TVS-2300 9psi DW72lb catless stock cat back sensed map enabled.hpt

[ngc1068]

Wonder if it could be under Transmission/Torque Management/General/Snub TqLim Enable.... mine is set to 59mph....In 3rd gear the vehicle speed is way over 59mph by the point the engine operating condtions (RPM, PR, etc) reach the conditions region where this occurs, in second gear its well below 59mph? Thinking about maxing that value out... when I raised the max engine torque I got a dash full of ESP bas lights and no improvement, so put that back to stock.

[ngc1068]

Update...think we're onto something... noticed torque limits for 1st and 2nd gear were 500 ish... decide dto raise them up 3000+ to match gears 3, 4 and 5... made a pull, no problem, hauls ass like it should. Need to adjust VE cells for WOT now at those high PR's and RPMs now that I'm getting good WB data there... will update with a new log soon

Update with log, pull this time 1st through 2nd... yes its way rich, but that was intended... I think this problem might be solved, time to relax, can fine tune fueling and spark tomorrow hopefully!!! Thanks for all the help everyone.

23-05-19 20-46-01.hpl

Can't figure out why this wasn't a problem with the old ECU and the Diablosport tune that was in it... the low torque limits had to be there in the TCM at that time, right? The TCU is a different module that I didn't replace? Maybe this new ECU with newer OS has some newer algorithms that weren't fully functional back in the old ECU /old oS?

[rays04gtx]

Haha, okay, I guess I?m getting warmer? Do you think that value could be causing my issue? Would you mind advising on how I should go about adjusting it? Sorry to be a nag, I?ve worn out google and the forum advanced search and keep getting nothing helpful. I do sincerely appreciate the help!

YES, NO I wouldn't mind, you're not a nag, .

But You seamed to figure it out

Those parameters were most likely changed in the original Diablo tune, but when all the rewriting happened , they just didn't make the trip...Odd I know, but it happens.

[LilSick]

i think i see it : )

make another log with output shaft rpm in the channels

actual spark as well if its avail

[LilSick]

But You seamed to figure it out

his torque is getting cut in half

injectors are dropping

5.19a.png

[PurpleRam]

his torque is getting cut in half

injectors are dropping

5.19a.png

Fundamentally, yes, it's "fixed" but there is still an Injector Issue, time stamp 2:11.278 # 4 then #7 Injectors drop off , looks to me like they are not flow matched...... #4#8 peak at 18, #2&#8 jump to 18.1&18.2 , while #'s 1,3,5 are 17, #7&#6 are 17.5 and 17.6 ,
@2:14.198 he's off the Accelerator pedal ,and everything does their thing.


Let's try 2 more pulls, and 3 or 4 "3/4 pedal hits., see if the issues repeat or changes a little.



Ok I just went back and rewatched it again ,from 2:11.097 to 2:11.312 Inject duty is over 87.7, peaking at 94.4 @ 2:11.271 124% Ve , is too Rich, it's over working the Injector , fuel Flow rat takes a hit at that point also, peaks at 225lbs/hr, then drops down to 7.8lbs/hr

Get the AFR under control and you should be good to go........(still think the injectors are not flow matched correctly)

[ngc1068]

Did some work on getting fueling dialed in... made a few pulls, smoothed out the whole VE table, anyway, here's second to last pull I made in 2nd.

23-05-20 14-11-58.hpl

I made another paste %/half from the above log, ran it again, and decided I'm happy for now. Its logging AFR's in the 0 to -10% range in the high PR cells now. Its hotter than F today here, Houston, its 90+degrees, and IATs are 160+, not gonna push it.

[ngc1068]

Fundamentally, yes, it's "fixed" but there is still an Injector Issue, time stamp 2:11.278 # 4 then #7 Injectors drop off , looks to me like they are not flow matched...... #4#8 peak at 18, #2&#8 jump to 18.1&18.2 , while #'s 1,3,5 are 17, #7&#6 are 17.5 and 17.6?

Car was shifting in this time frame, this pull I wanted to log how the engine and transmission would behave for a WOT shift.

I guess from all this I wonder how exactly does the transmission communicate demands to limit torque to the ECU (like is it a discrete on/off?i.e. hey, Me ECU, STOP making torque!!?or is it analog, like hey Mr ECU, please reduce torque by x amount)?also how does the ECU limit torque? Obviously it shuts off injectors in some kind of round-robin approach?looks like it also reduces timing?

Sorry for so many questions!

[PurpleRam]

More of the analog situation, unless it’s too rapid of an increase, the ecu’s 1st step at limiting Tq is spark, keep in mind the mopar way of thinking is all Tq/airflow, the computer use gs/second to determine Tq

[ngc1068]

More of the analog situation, unless it?s too rapid of an increase, the ecu?s 1st step at limiting Tq is spark, keep in mind the mopar way of thinking is all Tq/airflow, the computer use gs/second to determine Tq

I get that, but I am not asking how the ECU manages torque, I?m asking from which computer does the decision to limit torque arrise when the transmission is overloaded? Does the ECU decide, or does the a TCM decide, and if its the TCM, how is the request communicated to the ECU? I imagine it is the TCM that decides, and communicates over CAN bus the request to the ECU via some discrete or integer or floating point variable, or a combination.

[LilSick]

"when the trans is overloaded" ???

[ngc1068]

"when the trans is overloaded" ???

Yes, is this not obvious? The TCM has a table populated with maximum allowed torque in each gear. Torque is most often considered a load, rather than a source ... you cannot apply torque to an arm with no resistance... it requires a force x a distance, or work per revolution, etc.... so... anyway, I'm using the term overload to mean... the condition has been reached where the calculated torque output of the engine is exceeding the values in the table... at this point, something, some logic solver, the TCM, or ECU determines the threshold has been reached, and somehow communicates this event to the ECU and the ECU responds by pulling timing, and cutting off injectors. I'm just curious how this interaction between the TCM and ECU actually works. Its perfectly okay if nobody knows the answer.

[PurpleRam]

I get that, but I am not asking how the ECU manages torque, I?m asking from which computer does the decision to limit torque arrise when the transmission is overloaded? Does the ECU decide, or does the TCM decide, and if its the TCM, how is the request communicated to the ECU? I imagine it is the TCM that decides, and communicates over CAN bus the request to the ECU via some discrete or integer or floating point variable, or a combination.

The ECU "decides" the TCM tells the ECU , that Tq is reaching a set Limit, then the ECU backs off power by Limiting spark.

[CaliberGuy05]

Hello,

I had a problem like this as well. my car is not the same as i drive a dodge caliber. But if this helps i disconnected the speed sensor and was able to get passed the limit. I would also like to figure out where this setting would be at. it feels like a limiter.

[ngc1068]

Hello,

I had a problem like this as well. my car is not the same as i drive a dodge caliber. But if this helps i disconnected the speed sensor and was able to get passed the limit. I would also like to figure out where this setting would be at. it feels like a limiter.

Hi I have no experience with tuning the Caliber, but I feel like I ought to give an update to close this thread out.

My issues all turned out to be related to settings in the TCM. With my change of ECU, I ended up inadverently flashing the TCM back stock, (the TCM had a non-stock tune it in which came with an ECU tune when I flashed the car with a DiabloSport Predator flashing tool, which had calibrations designed to modify the ECU and TCM for operation with the supercharger that I installed back 10 years ago)....anyway... when I flashed the ECU back to stock with the Predator (to unmarry it from the VIN), I unknowingly at that time had flashed the TCM back to stock. Fast forward to having flashed the new replacement ECU with the proper calibration, I only had the ECU calibration to flash into it, no TCM... so with the supercharger and properly tuned ECU... the car still didn't behave 100%. I didn't realize for awhile, that the issues were caused when the stock calibrated TCM felt it was receiving too much torque (and it was of coure due to the supercharger and probably 80% more power and torque than tock) and thus issues were TCM limiter based. I probably wasn't searching for the right things, because I didn't know enough to suspect the TCM was upset. I didn't see anything in the forums that clearly warned an idiot like me that if you see injector pulses go away... it could be an obvious sign the transmission was telling the ECU to stop making so much damned torque, and the ECU stops making torque by shutting off some injector pulses. I haven't found any PID's to monitor in my Challenger that directly indicate there is a TCM limit condition happening.

It seems that in my car if the ECU is being commanded by the TCM to limit torque, the ECU limits torque by intermittently and in a round-robin sort of approach, shutting off injectors. You can see the commanded mSec for various injectors go to zero for extremely short intervals when the TCM was upshifting in both part and WOT. Once all this became obvious, and I understood what had gone wrong (I had lost the TCM settings for supercharger operation!)...I basically was faced with having to redevelop on my own, some sort of new TCM settings to work on this supercharged car.

The fix for my woes was nearly all in the TCM... first: to raise the values up to max 4999.98lb-ft of torque in Trans/TorqueManagement/General/TorqueLimit/ vs. Gear for 1st, 2nd Gears (note on my car, 3rd, 4th and 5th were already set pretty high)... that change solved the WOT limiting in 2nd Gear that I was experiencing. Secondly, I had noticed an annoying stutter or hard, kind of erratic, up shift when under mild or medium part throttle acceleration. The fix for this was under Trans/TorqeManagement/Upshift/TorqueReduction/ and I had to set all 5 of the TqRed1-2/2-3/3-4/4-5 to DISABLE. Now the car drives like it should, upshifts hard under WOT, and upshifts perfectly crisp and smoothly with no stutter under part throttle. I had no problems with the way the car behaved under deceleration. I'm sure there are many other settings that could be and probably should be further optimized in the TCU, but at this point I'm relieved and I'm very happy with the way the transmission behaves now.

[PurpleRam]

Thanks for the update