08 Denali - 6.2 Swapped to 5.3 tuning help

I never wanted to be that guy, the one that just wings it when learning something new, but here we are.

Anyway.. I need help with getting it running in a richer direction, and now I'm way over my head I feel.

2008 GMC Yukon 6.2 AWD. The 6.2 started making a noise and upon changing the oil found it had made glitter. Not wanting to spend the money on a Junkyard 6.2 I opted for the cheaper 5.3. I've done the following "upgrades" (might still be a net loss here, but whatever. :yay:) The truck was running good before I did the exhaust, but I wasn't happy with the performance out of it. I've been slowly tuning it down to being a drivable vehicle, it still has some hesitation at all throttle inputs and especially when cruising. Most recently it has been going extremely lean, 23+.

Attachment 143449Attachment 143450Attachment 143451Any help would be much appreciated. I've attached my most recent "tune", and the log from that tune.

2007 5.3 LMG block 0 VIN code, stock 243 heads, e85 injectors, pushrods

DOD deleted - new stock lifters
Summit Racing SUM-8718 205/217 112+2, .500/.500 lift
RockAuto trunnion rocker arms
Speed Engineering full exhaust 1 3/4" headers 3.5" the rest of the way back
AEM wideband 30-0334X
HPTuners ProLink+

Thanks in advance,

Jonny

By 'e85 injectors' does that mean 2007 LMG/LC9 injectors, #12594512, 34.6lb? Because the file definitely does not have the correct data for LMG injectors, it's got data for 29.4lb non-flex 19421333's.

Quote:

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Originally Posted by blindsquirrel

By 'e85 injectors' does that mean 2007 LMG/LC9 injectors, #12594512, 34.6lb? Because the file definitely does not have the correct data for LMG injectors, it's got data for 29.4lb non-flex 19421333's.

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That is correct, it is the stock e85 injectors. It would be best assumed that I know nothing of tuning or how to set up a tune. I didn't even know there was a place for this information.

And again, just to be sure we're talking about the same thing when we're using different names for them, stock injectors means stock for the 2007 LMG?

Quote:

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Originally Posted by blindsquirrel

And again, just to be sure we're talking about the same thing when we're using different names for them, stock injectors means stock for the 2007 LMG?

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That is correct.

Attachment 143452

Data taken from:
Attachment 143453

I'm trying to not assume, but the goal here is to update my tune to match the one you provided? If so, I'll leave the Torque management alone as I'm running a 6L80e

I took your file, that you posted, and then copied in the correct data that matches the 12594512 injectors. Nothing else was touched in the file (you can open both of them in 'Compare' mode and see the changes), you can flash that exact file as-is. It's your file already. You do not need to copy anything into any other file.

DO NOT flash the 2008 Avalanche file, that is just the source for the injector data in case you wanted to see it.

Quote:

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Originally Posted by blindsquirrel

I took your file, that you posted, and then copied in the correct data that matches the 12594512 injectors. Nothing else was touched in the file (you can open both of them in 'Compare' mode and see the changes), you can flash that exact file as-is. It's your file already. You do not need to copy anything into any other file.

DO NOT flash the 2008 Avalanche file, that is just the source for the injector data in case you wanted to see it.

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I understand now. Thank you for clearing that up. I wasn't going to flash anything until I got clarification, this is already a huge headache.

It’s now running lean on idle and under acceleration. It won’t accelerate without stumbling and the AFR gauge reads - - - - which would be over the highest number I’ve seen of 28.3.

I wasn’t able to get a good log before church. I’ll try and get a log after and upload it

You probably need to start over with a stock file, except for the injector data and DOD turned off. If you made fueling adjustments based upon incorrect injector data, all of your “adjustments” are useless.

I thought about that as soon as I posted that. So I rebuilt the tune from scratch using the new injector data. I also removed 4 degrees of timing from the base High octane table.

I'm getting some decent data logs but I am concerned with it going to too lean as every time I update the VVE table the AFR gets leaner, as expected, how do I counter excessive lean conditions? This last tune would idle in gear at an AFR reading of 18.0, in Park or neutral and the AFR would be 13.8-14.5.

Also while under acceleration and cruising it stutters, falls on its face, and acts like a bad coil pack under 2000 RPM. It does do this above this, but is not as consistent. Is this something normal while tuning? or could there be a different underlining condition, i.e. base high octane spark table.

Included newest tune and log file
Attachment 143509Attachment 143510

I think it would be a real good idea to tune the closed loop parts of the tune in closed loop using fuel trims, and forget all about the wideband for now. Once the CL is responding you can use trims as a sanity check for your WB.

Quote:

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Originally Posted by JonnyS

I thought about that as soon as I posted that. So I rebuilt the tune from scratch using the new injector data. I also removed 4 degrees of timing from the base High octane table.

I'm getting some decent data logs but I am concerned with it going to too lean as every time I update the VVE table the AFR gets leaner, as expected, how do I counter excessive lean conditions? This last tune would idle in gear at an AFR reading of 18.0, in Park or neutral and the AFR would be 13.8-14.5.

Also while under acceleration and cruising it stutters, falls on its face, and acts like a bad coil pack under 2000 RPM. It does do this above this, but is not as consistent. Is this something normal while tuning? or could there be a different underlining condition, i.e. base high octane spark table.

Included newest tune and log file
Attachment 143509Attachment 143510

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This appears to have a miss on the drivers side.

Keep an eye on fuel pressure too. It's lower than ever should be (35psi)

Okay, so I've put in a new fuel pump and did find that the exhaust manifolds were leaking and fixed those as well.

I've started over with a clean stock tune. I've made these adjustments to the tune:

Adjusted idle speed
turned off VVT/DOD
changed injector flowrate vs Press for 5.3 injectors
changed Mult vs RPM burst knock retard @1000 from .850 to .550
changed VVE back to match stock numbers
set timing -4 over whole table

It doesn't seem to be running any better.

It still has a miss that causes a lean condition on both banks. I can't think of anything else that would cause this issue.
The log does show the Narrow bands going lean, and when this happens the spark degree oscillates and is not smooth, the injector duty oscillates, and the RPMs aren't smooth either.

I'm not sure what I'm missing here...

Also since I'm running in closed loop, do I update the VVE table in the same manner that I was doing it in Open loop? I'm not sure how to adjust fuel trims using closed loop.

For some reason, its not letting me upload my log file. I'll try again in a couple of hours.

Attachment 143776Attachment 143777

It wouldn't allow me to attach the first log I got driving it, but I was able to attach the second log I got. Attachment 143779

I was also just thinking about this, when I first swapped the motor to a 5.3 I hadn't done the exhaust yet, but the truck was running okay. It wasn't until I put on the headers and removed the cats did I start having this issue. Have I not turned something off possibly?

Did you change the rest of the injector data?

The flow rate isn't enough. You need to to the flow rate, min injector pulse, short pulse adder and offset vs volts data. All of that needs to be changed for the injector data to be correct.

Just a FYI, negative trims means it's rich and not lean. It's pulling fuel to make it run correctly.

Quote:

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Originally Posted by 5FDP

Did you change the rest of the injector data?

The flow rate isn't enough. You need to to the flow rate, min injector pulse, short pulse adder and offset vs volts data. All of that needs to be changed for the injector data to be correct.

Just a FYI, negative trims means it's rich and not lean. It's pulling fuel to make it run correctly.

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Yes, I made all of the injector data match the injector data BlindSquirrel provided previously.

I've been comparing my stock 6.2 tune tables with some 5.3 stock tunes I found in the REPO. They are way different.

Things like the following tables:
Spark>Advance>

• Base> High Octane/Low Octane
• Piston Slap
• Fuel>Gas
• IAT
• ECT
• VCT
• Max Torque Timing
• Idle Spark Advance>Base/Coastdown
• Idle Spark Adder>Mult vs. Baro
• Overspeed>P/N, Gear, Coast
• Underspeed>P/N, Gear, Coast
• Startup>Multi
• Minimum Spark>Base

Knock Sensors>Knock Sensor Level> Multipliers>1-8

Fuel>General>
Octane Scalar Delta, (.401 vs .301)
Offset>Offset vs. Press vs. IGNV
Pulse Corrections>Short Pulse Adder
Injection Timing>Boundary

Fuel>Open Loop/Base>OpenLoop>Gas (Gear) / Gas (P/N)
Fuel>Open Loop Gains>IVT Gain Gas / InjTemp Gain
Fuel>Power Enrich>Delay>Enrichment Timer
Fuel>Power Enrich>Power Enrichment>EQ Ratio (Gas)
Fuel>Cutoff, DFCO>

• Cylair>Enable/Disable
• Throttle>Enable TPS/Disable TPS
• DFCO Exit Spark>Blend Time/Exit Spark

Fuel>Transient>Transient Fuel Mass Gain>Impact Factor>Accel/Decel ratio

Airflow>General>MAF Calibration>Airflow vs. Frequency
Airflow>Dynamic>Prediction Coefficients> Base/Current/Corrected
Airflow>Dynamic>VE Correction Factor>Initial
Airflow>Speed Density>Dynamic Airflow>Manifold Volume (14,000 cm3 vs 11,700 cm3)
Airflow>Speed Density>VE Coefficients>Constant

• Map
• Map2
• Map.RPM
• Map.IntakeCam
• RPM/RPM2
• RPM.IntakeCam
• IntakeCam
• IntakeCam2

Do any of these tables scream that I need to make my tune match the stock 5.3 tune?

Would any of these tables being so different cause some of these issues I'm having?

I'm just throwing everything at the wall and seeing what will stick. I just can't afford to hurt this motor as it's my daily.

It's not a good idea to just blindly dump data in.

Set thing things you know you have in the tune. Like injector data, displacement, etc.. then tune away. The VVE stuff could likely be ported over as long as you handle the VVT sections for what you have.

The log had a 103 maf code pending. When the MAF is so far out you can have this set. It really just needs a good tune.