E40/T42 no ISS Trans tune.

[jhbau1000]

I have a 5.3L swapped 06 Colorado with the original 13 wire Trans from Colorado. Having TCC control issues. Sometimes the TCC locks and sometime it don't. Sometime the trans will shift normally and sometimes it will shift 1<2 hard.

It will throw code P0741 - Torque Converter Clutch Solenoid Circuit Performance/Stuck Off if the TCC does not come on at driving speeds.

Cycling the key on/off will cause the trans to act fine for the first time through the shifting pattern 1<2 2<3 3<4 and TCC locks. After that is goes crazy it will hard shift and may or may not TCC lock.

E40, ECM, GM Gen4 V8 - OP 12612557
T42, TCM, GM A4 - OP 24235341

[TransGo Robert]

Once the computer detect the excessive TCC slip it tries to protect the unit by commanding max line pressure and eventually will also stop trying to apply teh lock-up completely. Lets see a log of your data so we can try to diagnose the TCC lsip issue.

[jhbau1000]

Here is the log from my last drive around and updated tune. I did make some changes based off another post I found here on HPTunes forum. It seemed to help a little but if it throws code P0741 - Torque Converter Clutch Solenoid Circuit Performance/Stuck Off than that it. It will not apply TCC for that drive cycle.

[TransGo Robert]

Here is the log from my last drive around and updated tune. I did make some changes based off another post I found here on HPTunes forum. It seemed to help a little but if it throws code P0741 - Torque Converter Clutch Solenoid Circuit Performance/Stuck Off than that it. It will not apply TCC for that drive cycle.

Ok that's not a tuning issue, it is an internal problem with the transmission. Most likely the usual wear at the TCC regulator valve bore in the valve body. It does manage to lock under very light load but as soon as you put little bit of throttle into it it can't hold even with the commanded locked up pressure maxed out. The fluid was at 160 F or so which is usually when they start acting up when the valve body is worn out, if you get it up to 180-190 F it will get much worse.

[jhbau1000]

This is the same transmission we went though yesterday TransGo Robert. I made a new post hoping to get some answers. Trans was rebuilt by local shop and has less than 1000 miles on it, but I will check back in with them on Tuesday to see if they can help. This is a known issue with the 4l60E 13 wire no ISS sensor. I think the problem is that the computer cannot calculate the slip properly. With no input sensor I'm not sure how it calculates the slip rate. I don't think the TCC is slipping but the computer says it is and kicks it out then throws a code to keep it from trying again. But this is just my guess at this point. It very well could be the valve body. Also I noticed that the TPS is reading higher than I would expect. Its seem to be showing 30-40 % when I'm not pushing that hard on the pedal.

[TransGo Robert]

This is the same transmission we went though yesterday TransGo Robert. I made a new post hoping to get some answers. Trans was rebuilt by local shop and has less than 1000 miles on it, but I will check back in with them on Tuesday to see if they can help. This is a known issue with the 4l60E 13 wire no ISS sensor. I think the problem is that the computer cannot calculate the slip properly. With no input sensor I'm not sure how it calculates the slip rate. I don't think the TCC is slipping but the computer says it is and kicks it out then throws a code to keep it from trying again. But this is just my guess at this point. It very well could be the valve body. Also I noticed that the TPS is reading higher than I would expect. Its seem to be showing 30-40 % when I'm not pushing that hard on the pedal.

Funny I did not realize it was the same one. Lol

The log from yesterday must have been taken cold (out for a walk with the dog I can't go look an confirm it now) because the three times it commanded it to actually lock it did lock. In this one it commands it to lock but it just can't hold under load. The calculation is correct, you have it setup to ignore the missing ISS sensor, so it is simply multiplying the OSS RPM by 0.70 to infer what the input shaft speed is. You can do the match yourself or even create a math channel for it if you want, you will see it is spot on. If you get it up to 180 F or so you will see it will get much worse. This is daily easy to fix in the valve body, it is by far the lost common issue with the 4L60E.

[jhbau1000]

Ok, what i will do is put the tune from yesterday and make a new log with trans temps up . I'm still not sure how to even read the log to know what i am looking for.

[TransGo Robert]

Ok, what i will do is put the tune from yesterday and make a new log with trans temps up . I'm still not sure how to even read the log to know what i am looking for.

When I get back home I'll take a couple of screenshots and explain how to look at all this. I think the way you had it setup yesterday it just was not asking for lock-up unless the load was very light. So that masked the problem and made me think it was a command issue. The log from today is crystal clear, this is 100% sure a problem in the unit, not something you can fix with tuning.

[TransGo Robert]

OK so I looked at the log from yesterday or the day before and it was all the way up to 200 F, the difference was not the temperature it was simply the way you had your tune set up. It would only command lock-up under super light load so it was able to hold for a second or two while it was commanded. Now with a more normal command the problem shows its ugly head. I have the various PID grappend in the following screenshot, one is a modified PID that allows to show 0 when the TCC enable solenoid is commanded OFF and and a 1 when it is commanded ON so that the data can be graphed. I also made a math channel that takes the OSS reading and multiplies it by 0.70 (Overdrive ratio) so that when in 4th it calculates what RPM the input shaft is turning. On the first screenshot I circled in light green when all was fine. You are at 17% throttle or so, you can see the computer calculated slip is just about zero the hole time which is confirmed by my math chanel where you see the ISS calculated (Yellow graph) is identical to the engine RPM (yellow graph). Then on the second screenshot you can see where I circled red the problematic area. You increased the throttle to 34% and now the converter clutch just can't hold and the calculated slip goes above 130 RPM. It is again confirmed by may math chanelle, you can now see the red and yellow line no longer ride over each other.
Good.pngBad.png

I hope this helps, it is not all that easy at first to graph all the PIDs and make sense of it all. If you have any questions, let me know.
PS When all is well it the transmission, it takes no more then 50-60 % to keep the slip at 0 RPM.

[jhbau1000]

Thanks you. I sure wish I knew how to get my chart layout like yours. It makes it easier to read that way. How did you modified the PID that allows it show 0 when the TCC enable solenoid is commanded OFF.

[TransGo Robert]

Thanks you. I sure wish I knew how to get my chart layout like yours. It makes it easier to read that way. How did you modified the PID that allows it show 0 when the TCC enable solenoid is commanded OFF.

It took me forever to find a way to change PIDs that won't graph because they are in text instead of numbers. Here's how I do it, It is a pain but when you need it at least it is doable.

First open the log file and then go to top left, click on Log File and then in the drop down click on Export Log. In the window that opens select Comma Separated Text (.csv). and save the file to your desktop.

Next open the file in Excel or whatever you use for spreadsheet and find the PID you want to change. Once you find the PID you will see a number above it, right it down somewhere, you will need it later.

Next select the entire column for that PID and do Ctrl+H on your keyboard to bring up the find and replace box. From there you have to do a find and replace for all the texts before ON and OFF that appears in there and replace it with nothing. Leave the replace box empty.

Next do a find and replace for OFF and replace it with zero and finally a search for ON and replace it with one.

Now save the file. The problem here is if you try to open this new file in HP Tuners it will not works because Excel add a bunch of ,,,,,,,, in there for the first few lines. So you got a get rid of those... open the file but this time using notepad instead of Excel. Now highlight one of those long strings of commas ,,,,,,,,, and again do Ctrl+H. Paste what you have on your clipboard into the find box, leave the replace box empty and do replace all. Now close and save the file.

Now drag that csv file back in to HP Tuners (click, drag and drop it in) and the file will now be in HP Tuners like before but this time showing 0 and 1 instead of text for that PID. But wait, we are not done.... I did say it was a pain so we have two more steps to do...

Go into tools and create a new Math Parameter. Give it a name of your choosing, abbreviation, etc and then in the box where you would normally put the formula enter the PID parameter ID you wrote down earlier putting it in between two square brackets and save it. In this case it would be [14102].

Last step simply right click your chart area and open the chart layout box. Add a new parameter, and go down the list all the way to the bottom to "user defined" and you will see your newly created math channel there. Adjust the color and scale to yur likcing and ther you go you can now graph that PID.

Did I mentioned it was a pain to do? LOL

[jhbau1000]

Yes that does suck. Looks like they should allow you to do something like this : [14102]="4th TCC On" And set the Units = One()

[TransGo Robert]

Yes that does suck. Looks like they should allow you to do something like this : [14102]="4th TCC On" And set the Units = One()

Yea that sure would make it easy. But all the match formula work with numbers only from all that I have tried. It did ty with quotation marks, without it, no difference nothing works unless I go to the trouble of changing the text to numbers myself. If there is a way to do it, I sure don't know how.

[jhbau1000]

Here is my latest log. TransGo Robert if you have time to review and see if the TCC slip is still there. From what I can tell it is.

[TransGo Robert]

Here is my latest log. TransGo Robert if you have time to review and see if the TCC slip is still there. From what I can tell it is.

Yep, it still slip.

[jhbau1000]

That's what I was saw to. Why does the TCC PWM Duty Cycle come on and off when its not calling for TCC? Can you tell by this log if the 1-2, 2-3 ,3-4 is slipping to. Trying to get everything together so I can go by the shop that built this transmission. I have noticed and you can see in this log the Trans temp goes from 171 to 181 in this short trip. That's seems high its not that hot outside and it has a trans cooler on it too.

[jhbau1000]

Also I did a pan drop and new fluid & filter change last week. Found nothing in pan but fluid was very dark brown all ready.

[TransGo Robert]

That's what I was saw to. Why does the TCC PWM Duty Cycle come on and off when its not calling for TCC? Can you tell by this log if the 1-2, 2-3 ,3-4 is slipping to. Trying to get everything together so I can go by the shop that built this transmission. I have noticed and you can see in this log the Trans temp goes from 171 to 181 in this short trip. That's seems high its not that hot outside and it has a trans cooler on it too.

The duty cycle goes up to 95% or so as soon as you start rolling, that's just to keep fluid flowing through the solenoid to keep it clean and warmed up ready for the command later on. Everytime the computer thinks it is about to command lock-up it first goes to this "Apply En Delay" phase where it drops the duty cycle down to 9% or so in preparation for when the ON/OFF solenoid will be commanded to turn ON. But in the log you kepong on changing the throttle position, so many times it aborted right when you released the throttle so it never commanded the ON/OFF solenoid to turn ON and went back up to 95% to be in waiting mode until the conditions are right again to command lock-up. As for being able to tell if the transmsision itself is slipping, without an input speed sensor you cannot tell with certainty. It will just show up as TCC slip because the computer just assume that's what slipping. But looking the engine RPM drops on each shifts I don't see anything there that would lead me to believe that there is slip in any gears.

[TransGo Robert]

Also I did a pan drop and new fluid & filter change last week. Found nothing in pan but fluid was very dark brown all ready.

Yea no surprise with the clutch constantly slipping like that in the converter that degrades the fluid real fast. That's also why your temperature goes up quickly. With the clutch fully locked there is not much heat being generated in a transmsision, but when it is not fully lock that cooler has to work hard to dissipate all abnormal heat generated.

[jhbau1000]

Ok new torque converter and transmission shop did some work on valve body. This is my l latest log. I did have to go in tune and set P0741 - Torque Converter Clutch Solenoid Circuit Performance/Stuck Off to not report or it would lockup one time and quit until next drive cycle. 23-10-01 14-45-56.hpl