L83 / 8L90 Assistance Requested Jeep Swap

Good Afternoon everyone

I am looking for some assistance in getting my L83/8L90 to be behave.

Backstory: I swapped a complete pull out from a 2017 Silverado 4x4 into a 2008 Jeep Wrangler. I used a motech swap kit to move everything over. Once I got everything situated and fired up I had some issues with the 8L90e shifting correctly ? after a flush and proper fill it was running great. I was able to make a few 5 mile test drives.

Once I felt like it was running well, I took the family for a ride- that?s when the problems started. It seems to idle ok, as soon as I shift into gear, it stalls immediately unless I floor it. By looking over the scans, the LTFT is high on both banks. This would indicate that a vacuum leak is present.
As part of the swap a new MAF and O2 sensors were used. The PCV, Purge solenoid and other items were re-used. Original mileage is believed to be 30K.
I have smoked the intake ? no leaks other than some small wisps from where the MAF mounts to the intake were found. I also smoked the exhaust to make sure I didn?t have any fugitive air getting sucked in and providing false readings- no findings there either (I didn?t think this was the issue as both banks read the same or so).
The other areas I have inspected (meaning plugging the area and looking to see if trends improve) are the dipstick o-rings, Filler Cap, brake booster vacuum hose, PCV hose leading to the intake, and purge valve.

The tune attached is the tune supplied by motech - the only change i have made was to input the tire and gearing using the wizard.

Wanted to get some input on the tune and scan prior to throwing cash at replacing parts blindly until improvement is seen.

Thanks for your input in advance.

The tune you posted is calibrated for a 6.2l. Is the ecm from the same truck?

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Originally Posted by SILV

The tune you posted is calibrated for a 6.2l. Is the ecm from the same truck?

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Wow. Interesting find. I didn't mention that getting the pull from the yard was a complete cluster. The originally supplied at T87 instead of the T87A. Wouldn't be surprised if the ECM was not matched to the engine.

Is that an easy fix? I am new to the "in depth" tuning in the past i have used the tuners with "pre-packaged" tunes.

Thanks!

There is also no trans calibration in that file. Need to read them both in.

I have both the T87 and a locked T87A - any experience with a a T87 playing nicely with a 2017 8L90? I just havent sent the T87A off yet as I was unsure if I could run it on the T87.

Quote:

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Originally Posted by LoneStarJeep

Wow. Interesting find. I didn't mention that getting the pull from the yard was a complete cluster. The originally supplied at T87 instead of the T87A. Wouldn't be surprised if the ECM was not matched to the engine.

Is that an easy fix? I am new to the "in depth" tuning in the past i have used the tuners with "pre-packaged" tunes.

Thanks!

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Yes I have seen guys running the T87 in place of the T87A with a 2017 ecm.

I would start by copying over all the l83 Maf and VVE data over. Also cylinder, injector control settings, and throttle data. Do these first then test it out. These will throw off torque calculations and may be some of your transmission issue. There is a 2017 l83 file in the repository but it has a 6l80e trans file attatched. The ecm data should still get you going.

I have used a T87 on a 2017 L86, 8L90E truck. I bought the T87 new, installed it in a 2015.5 rig with the same motor, trans and gear ratio and programmed it with GM tools. Then I installed it in the 2017, read it and tuned it.

Happy Friday everyone. I have re-installed the T87 and removed the locked T87a

I modded the tune as suggested. LTFT is looking much better. I appreciate the advice thus far. Engine is idling much better based upon the changes made.

I am still stalling shortly after shifting into gear I attached a VCM scan of the crank, idle and shift into gear.

only things that stick out to my untrained eye is the MAP and MAF readings.

All assistance is appreciated!

Go to the idle table. Copy all the idle settings over. Then do the same for the idle torque section.

I used to work at motech. I can do live tuning to get you setup. [email protected]

There are a lot of things that need tweaked in your tune.
Are you running a fuel pump control module?
Active grill shutter?

I would download a stock l83 5.3 tune and copy over al lot of the basic stuff. Looks like you have a 6.2 calibration.