2018 L83 6L80 swap Negative timing issue

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09-08-2022
2stimpy

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2018 L83 6L80 swap Negative timing issue

On my 2018 l83 swap I have big negative timing issues.
It seems to drive good until it shifts.
After each shift at part throttle it starts commanding as much as -20 degrees of timing and I can hardly accelerate.
I can't seem to figure out what is causing this to happen.

If I pull the MAF connector and reconnect after about 10 seconds the engine runs noticeable different.

After doing this it is running much better and it is not commanding the negative timing anymore.

What am I missing.

Stock engine with open air intake.
I have tried MAF tuning but with no success.
09-12-2022
2stimpy

No one who can help me even a bit?
A new MAF did not solve it.

I am going to try sd only and see if it drives normal in sd mode.
But if it does I still have no clue on what to look for.
09-12-2022
howeverthe5oh

Quote:

Originally Posted by 2stimpy

On my 2018 l83 swap I have big negative timing issues.
It seems to drive good until it shifts.
After each shift at part throttle it starts commanding as much as -20 degrees of timing and I can hardly accelerate.
I can't seem to figure out what is causing this to happen.

If I pull the MAF connector and reconnect after about 10 seconds the engine runs noticeable different.

After doing this it is running much better and it is not commanding the negative timing anymore.

What am I missing.

Stock engine with open air intake.
I have tried MAF tuning but with no success.

I?m not able to check the file but based on my experience try disabling torque management in the trans for the upshift
09-12-2022
howeverthe5oh

Quote:

Originally Posted by 2stimpy

No one who can help me even a bit?
A new MAF did not solve it.

I am going to try sd only and see if it drives normal in sd mode.
But if it does I still have no clue on what to look for.

Email me at [email protected] I?ll help as much as possible
09-12-2022
SultanHassanMasTuning

stock engine or modded?
09-12-2022
2stimpy

Quote:

Originally Posted by howeverthe5oh

I?m not able to check the file but based on my experience try disabling torque management in the trans for the upshift

Quote:

Originally Posted by howeverthe5oh

Email me at [email protected] I?ll help as much as possible

Thanks, I will look in to that.

Quote:

Originally Posted by SultanHassanMasTuning

stock engine or modded?

Engine and trans completely stock, only different thing is the cold air intake with aluminium tube.
And of course no cats. Do have the front sensors and added the wideband.
09-13-2022
SultanHassanMasTuning

1 Attachment(s)

did you ever do a throttle relearn

with 2018+ you may need like SnapOn tool

i will review file

Attachment 124150

try
09-13-2022
2stimpy

Quote:

Originally Posted by SultanHassanMasTuning

did you ever do a throttle relearn

with 2018+ you may need like SnapOn tool

i will review file

Attachment 124150

try

Yes, i did do the throttle relearn a few times. I read some need to do this every time the update the tune.
After the first time I do not notice any difference anymore after doing so.

Thank you for your help, I will try your file and see what's the result.

I noticed changes primarily in the torque DOD tables. Does this indeed stil affect anything while DOD is turned of?
09-15-2022
2stimpy

Quote:

Originally Posted by SultanHassanMasTuning

did you ever do a throttle relearn

with 2018+ you may need like SnapOn tool

i will review file

Attachment 124150

try

This did not change anything.
The tune I got from CPTuning got me a little better results.

I also tried sd tuning which only worked with manually switching open loop to on and ltft to off in vcm scanner.
After doing this, it drove way better, but still get negative timing when I get on the throttle.
I did manage to get op to 60 mph in 6th.

I have a strange sound from under the dash which seems to be related to the fuel system.
Strange thing I noticed is that as soon as I set "command closed loop" to off, this sound disappears.
To hear it, set the volume to high and maybe use earphones. You can see me switching it on and off.

https://youtu.be/ktNTg2T9JPc
09-16-2022
GHuggins

What I'm seeing in the log is where torque management is pulling timing during shifts. Now if this is going away in SD mode, then your most likely problem is the MAF side of your torque model especially since you installed a different bigger intake tube. I also assume the MAF is located in a nice straight area of the pipe. I will say that the intake tube change requires a different Torque model and a slightly different trans shift timing setup. Otherwise you might notice it unlocking and locking the converter a lot and changing gears incorrectly because of it. If you just want a quick fix - set the MAF up to fail and drive it that way all the time. Only problem is these have to fail every key cycle so may see starting problems time to time. BUT torque model - shape from 1200rpms up for what you're after.
09-17-2022
2stimpy

1 Attachment(s)

In SD it runs a bit better, in that mode I can get up to speed and it shifts to 6th gear.
But even then when I push throttle timing is going negative.

Also, I can only get it in SD open loop by forcing this in the scanner.
Changing various settings does not make it run in SD.

The same thing with MAF only. I have to force that in the scanner.
Changed settings in the tune will not force it in to MAF.

sd log
10-01-2022
2stimpy

I found out the engine was running of the low octane table, I don't know why.
Copied the High octane table in to my low and now it drives fine, finally.

I still need to figure out why it runs on the low map, but it is time to start MAF tuning and go from there.

Sad thing is that I figured this out only after a few months trying everything else. Now winter is coming and the sub will be stalled for the winter in a month or so.
10-01-2022
5FDP

Probably runs off the low octane table because you have a P0330 code, that most recent log shows that code as well as a MAF/IAT code because of the speed density.
10-01-2022
2stimpy

I noticed the code also but on the scanner it shows as a permanent code, that shouldn't be a problem. I do not see knock or knock retard. Could the sensor be faulty? I read somewhere that they almost never fail.
10-02-2022
2stimpy

1 Attachment(s)

Today I successfully tuned MAF. Started about 14% rich after the 4th log i got it withing 3%.
During the drive I heard a strange noise that seemed to come from the exhaust. I don't know what knock sounds like. But it could be that.
In my logs I see no knock retard.
Another thing I noticed is that my coolant temp does not seem to go above 180 during driving. sometimes even lower while ambient temp is 65.
I do have p0330 current. Could this be the reason for not showing knock?(i ordered a new knock sensor just to be sure that the sensor is not the problem)
10-20-2022
2stimpy

1 Attachment(s)

I have chased a problem with my swap. and finally I found my problem. The engine was running on the low octane map which made the suburban undrivable.
The temporary fix was to copy the high octane map in to the low octane map.
I did have a few (permanent)errors from the beginning, one of them was Knock sensor bank 2(permanent).
Because I learned that "permanent" errors can't be erased and disappear on their own over time.
I did not take special care about this Knock error.
In the last logs I noticed that the error sometimes became "current".
Tracing the wire learned that the HPI 2017-2021 Gen V LT1 / L83 5.3/ L86 6.2 W/ 6L80E/6L90E 3 wire Standalone Harness had a cut wire in it.
The HPI harness also had another fault in their wiring. connections on the wake and ignition relay where switched. so the ecu never got power.

Attachment 125277
So please be advised never buy a HPI harness.