Hey guys, I just swapped a LS3 and 6L90e into my Cutlass. I cant seem to get the vehicle speed to read on the scanner nor does the transmission shift out of first. I have the same transmission in my Cutlass with a LY6 before swapping in the LS3 and it worked perfectly. I believe I changed from the old ECM to the new one but it still doesn't work. Please help.
Here is a copy of the tune I had prior to swapping in the LS3 and taking out the LY6
So you swapped computers too it looks like?
Why not just keep your truck computer that worked with the transmission and swap the parameters in the computer to match the new LS3.
The LS3 file has tons of other stuff done to it and much of it is unfinished. The MAP settings are different because it's a 2 BAR OS, the new VE tables are blank and it won't run right if you do that.
Also the 6L90e TCM was programmed for the truck computer and not the LS3 computer, it will not just work even though the camaro computer uses the same transmission.
Last edited by 5FDP; 01-13-2018 at 05:12 PM.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Well that was my next step but i'm not very good with changing the Injector parameters and it wont allow me to edit the Axis like it does with all the other tables so I'm not to sure where to start with that.Originally Posted by 5FDP
"Flow Rate vs. Press" is the I wouldn't know how to alter. Everything else I would be OK with I'm pretty sure
Last edited by ccrane0044; 01-13-2018 at 06:14 PM.
I just tried writing the tune for the LS3 onto the original (LY6) ECM and now I can't get the engine to start at all.
See attached for the tune.
So what exactly did you do?
Did you try to write entire over the original file or did you try to copy over the data?
The main thing you need to know is that the LS3 file you are using for reference is of a 2 BAR speed density tune, so it's not factory at all. If you copied over the tune, you will have incorrect information in there for some things like the MAP settings. A 1 bar map sensor does not use 200/8.33 linear and offset settings.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
I was able to get it to start but needed the throttle open and also ran very rough.
I copied over the data and wrote it that way.
Like I said some things are incorrect because it's a 2 bar OS. Input your stock MAP sensor settings back in or input the correct data for the 1 bar MAP sensor from the camaro if you are using the camaro sensor.
Input the data for whatever MAF sensor you are running, if you are still using the MAF data that was used with the truck PCM and not the card style MAF that a camaro uses, you need to revert back to that.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
So when I copied over the data and wrote the copied data to the original ECM it would run rough but the vehicle speed would work.
Once I tried writing the tune I read off of the LS3 ECM onto the original ECM it ran well but then I wasn't able to read the vehicle speed and transmission wouldn't shift again
I am using the Camaro MAP and MAF sensors. I changed the pins in the MAF connector to accommodate the new card style sensor along with adding the proper pigtail for the Camaro MAP sensor.
This engine has a cam in it from what I'm told. Would I still be able to input the stock MAF and MAP sensor settings?
You have to use stock settings as a base. The LS3 MAP sensor is 1 bar, you have settings for a 2 bar sensor currently, so you'll need to find a stock Camaro tune and copy over that data.
Once that is done you will have to completely re-tune the airflow model using the VVE and MAF curve for the new engine, new camshaft and whatever else you have done to it.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
OK, I'm not very familiar with how to change the Airflow model with the e38 ECMs. That's why I took the LS3 ECM in hopes that I wouldn't have to mess around with the tuning for the engine and was hoping just to adjust the transmission and everything would be fine. I am useing the MAP sensor that I got with the engine, does that make a difference at all? I got this engine out of a wreck and have no idea what cam it has or if there is anything else done.
Is there anything you can think of that would be causing me not to be able to read the vehicle speed with the LS3 ECM? I was hoping that would be a more simple route to go to fix my issue.
Last edited by ccrane0044; 01-13-2018 at 10:06 PM.
Now I'm not able to write anything to the ECM. I keep getting a failed message: "Controller unlocker: x36 exceeds number of attempts"
If you pulled the engine and transmission together and plopped them in the vehicle, it would likely function as normal because the 6L90e that was attached to the LS3 would already be "programmed" to run with that computer.
Just using the engine and computer but a totally different 6L90e with a totally different TCM and calibration from a LS3 vehicle is what will cause you many problems.
You not knowing what was done to the engine surely doesn't help you nor does not knowing what MAP sensor it was running. Get the part number and google it, it should tell you if it was a stock sensor or not. I did the search for you and if the sensor is a factory 1 bar LS3 sensor you need to input these settings for the linear and offset settings. 128.13 and -0.31. Depending on elevation and I'm going off of around sea level here, it needs to read around 100kpa with the key on engine off. If you live in the mountains it will be much lower around 90-95 or even lower. If it reads well over 105+ or something stupid like 170 you have the wrong settings for the MAP.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
I wan't to start with saying thank you for attempting to help me with this issue, I appreciate the help very much and hope this leads to me fixing the issues I am having.
That's what I originally did 6 months ago. purchased a wrecked truck and pulled out a low mile LY6 and 6L90e, used that harness (after de-pinning it) and that ECM, installed everything in my car, made some minor adjustments and changed the trans tuning to something more similar to the CTS-V (since they also use the 6L90e transmission) and everything worked great up until boxing day when I ran out of coolant due to a hole in the block. I didn't have the funds to purchase another engine and transmission together and due to mine being low mileage I figured it wouldn't be necessary. but now I can't seem to win. and this is my daily driver so having it off the road is making everything very frustrating.
As for the MAP settings, those linear and offset settings were the settings I had set in the tune during the scan that I posted above, when I was experiencing the engine running rough. Key on, engine off it reads 170 (can be seen at the end of the scan posted). In the tune that I read originally from the LS3 ECM the Linear and Offset settings are 200 and 10.34, should I try the same tune but with the same numbers from the LS3 ECM?
I'm assuming it wasn't only that causing the engine to run rough and that I will need to adjust the MAF settings as well? The MAF is what I don't quite understand how to tune (mainly the Airflow vs. Frequency table), and can't seem to find a good "how to" thread to help, which is why I was hoping I could use the matching ECM from the LS3, that way I wouldn't have to worry about causing harm to the engine by tuning it incorrectly. So now I'm not entirely sure how to go about this. With one ECM I have a good running engine but can't seem to read vehicle speed which is not allowing my transmission to shift out of first and with the second ECM I can read vehicle speed to allow the transmission to shift but have a improperly tuned engine.
Verify the sensor part number to make sure the MAP sensor settings are correct. I wouldn't put the 2 bar data in there just yet.
The VCM scanner section has several write ups on tuning the MAF and VVE for GEN 4 cars. Using a wideband will make things way easier.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
Thanks again 5FDP.
I'm back at the shop tomorrow during the day before starting my nightshift so I will have a look at the MAP sensor part number before changing anything. Hopefully I can figure everything out.
I'll have a look at the VCM scanner section for the write ups. I'm been meaning to get a wideband but things like this keep happening which take up all the extra funds and then some.
So the part number on the MAP sensor is 12591290
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