please help me understand what the crap is going on? (wastegates) : Resolved!!!

TopherSho said:
F$%k it.. I'm going to get a partial log right now,  it's easy to reproduce at mostly legal speeds for 2nd gear.   

3rd would be better and it would be in range of the issue longer but its to dark. well do that tomorrow.

If you wait a minute I'll rebuild the file and make it a fresh copy for shits and giggles.
 
To late.  i was out the door already :P

it had 3-4 VERY HARD stutters in third about 3/4 through the gear. I saw the RPM needle actually 'tick' back.  But do not see it in the log.

It did not hammer over and over like it did right after Pizaa... :P  i did not have the laptop hooked up so i wanted to keep the log i captured with hard stutters it did do.




 
I don't see anything in the log with my amateur eyeballs.  but again it wasn't hammering like it did a couple hours ago.  ... 

I was actually going to suggest we port the tunes by hand,  and create from scratch copies now that my handheld is updated.  But I REALLY want to get the data before I apply anything.  so build away,  but i may not apply it right away.

So here is a question,  i have backups of the stock tune from the SCT handheld.  Reverting to stock after the update did 'something' to temp fix it... if the tuner did go off the deep end do we trust the on-SCT device copy of the stock firmware?  Or should i see about getting SCT support to restore the backup i have to the device so i can flash back to a known good stock firmware?





 
Seems more a PCM issue than SCT, like the adaptives have kicked in ...  Can anybody lend an uptodate X4 for comparative purposes?
 
SHOdded said:
Seems more a PCM issue than SCT, like the adaptives have kicked in ...  Can anybody lend an uptodate X4 for comparative purposes?


I don’t have a problem lending my X4 but I strongly doubt that the hand held is the issue..

I would start looking at recording transmission PIDS. It’s sounds like perhaps the adaptives are causing problems in how the transmission is behaving...


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stealbluesho said:
SHOdded said:
Seems more a PCM issue than SCT, like the adaptives have kicked in ...  Can anybody lend an uptodate X4 for comparative purposes?


I don’t have a problem lending my X4 but I strongly doubt that the hand held is the issue..

I would start looking at recording transmission PIDS. It’s sounds like perhaps the adaptives are causing problems in how the transmission is behaving...


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Adaptives?  i have not done any research diligence into this.  Give me a short run-down?
 
stealbluesho said:
SHOdded said:
Seems more a PCM issue than SCT, like the adaptives have kicked in ...  ?

I would start looking at recording transmission PIDS. It’s sounds like perhaps the adaptives are causing problems in how the transmission is behaving...


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Mostly the adaptives in the trans settings are to help the PCM achieve the proper pressure for the desired slip times for the shifts...There really isn't anything that would "fight" the tune or make something revert back after a flash...The biggest things that are affected by adaptives is fuel corrections.

There is something esle odd and not sure if it's related but when you are spooling up in 1st gear your desired TIP and wastegate duty is really choppy. The RPM line in 1st and 2nd gear is pretty smooth but when you settle into 3rd gear the RPM gets choppy...Not sure if that's because you are sweeping through the revs slower and resolution is better.
 
(page 340 for my 2010) which states:

After a battery disconnect, the car must relearn idle and trim settings.

Start the car and let it come up to operating temp.
Turn on the A/C and let it idle for 1 min.
With the A/C on disengage the parking brake, place your foot on the brake and shift to drive, let it idle for 1 min.
Then drive the car over 10 miles.


Ok I did a KAM reset but did not do any of the specific steps.  I warmed it up, pulled the cable for 30 minutes and just drove nice.

I will do the needful on these extra steps.

@Brad,  on the rpm jitters.  that may be the closest were going to get to it logging the fluttering.  Fluttering is what it does around 4000+,  the more you push it hard in 3rd the flutter then gives way to outright stutters loss of power and stalling.
 
Wait, does the tach flutter on cruise with steady load?  That is usually a torque converter symptom.
 
I did it *one* time last night,  and AJP just advised my log showed my converter speed being jittery.

based on that and your comment,  I am going to spin up a new config file that gathers more tranny pids,  and keep gear, cam, load, throttle actual angle, rpm, oar, knock, misfire, sparkv2, bootskpa, boost-dsd, TQ src, wastegate % and add on MiL, DTC counter in addition to some other trans data points.

""Your torque converter speed ratio is all choppy to in the log during the 3rd gear...That's making me wonder if the converter is making the rpm choppy.""

what i need is new logging parameters with the issue going hard .. have not been able to nail it yet
 
TopherSho said:
? Are we thinking bad TQ converter ?


Would make sense... it started after the track right? When you launch from a dig your loading up that converter before moving... that’s a lot of stress.

Curious, what RPM where you launching from?

Only question is why does it not happen after a fresh flash? Only after a while?

When’s the last time you had a fluid flush for your transmission?


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stealbluesho said:
TopherSho said:
? Are we thinking bad TQ converter ?


Would make sense... it started after the track right? When you launch from a dig your loading up that converter before moving... that’s a lot of stress.

Curious, what RPM where you launching from?

Only question is why does it not happen after a fresh flash? Only after a while?

When’s the last time you had a fluid flush for your transmission?


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in order :
no idea,  i blew up my waste gates .. kinda over lapping behaviors
2200 on average and lower
I bet it is because one of the flashes coincided with me accidentally clearing the pcm when i pulled ALL the BCB fuses to scrape them shiny.


 
Edit:: I thought you mean the PTU :P,  SBS, I have 50k miles on the car.. maybe 150 races and about and equal number of hard launches..  I will see about checking the level and color and smell.

would you recommend adding the 1/3 to 1/2 quart OVER fill to prevent foaming and slippage?
 
SHOdded said:
Wait, does the tach flutter on cruise with steady load?  That is usually a torque converter symptom.

So far no, only under very sustained WoT load.    If the fluid is bad,  or low .. that may make sense that at higher rpm we start getting jittery / stuttery engagement as the fluid foams heats up or is 'spun to the walls' and not localized to some component?

... maybe .. spit-balling?

 
Grasping at straws here for you.  But if it is still acting up and you have not changed a bunch of things, maybe try a KAM clear with the handheld and see if it helps for a while?  Just thinking if it was an adaptive issue, that would show it conclusively.
 
well, to help eliminate the trans, a) make sure the fluid is perfect, and b) maybe top it off by a pint past the hashmarks (tip from LME to help prevent cavitation).  Too little mileage for TSS/OSS sensor or valve body/SBA involvement, but you say you have a lot of track mileage on the SHO, so the "true" mileage could be more than what the numbers tell us.  Some people are fanatical enough to change trans fluid after every track session, and have apparently reaped the benefits of doing so!
 
BTW, transmission adaptives IME do not change with a KAM reset, that is just the PCM portion.  The TCM / SBA portion has to be reset with IDS or similar highend scan device.
 
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