Need help with tuning 2016 Camaro 2SS Manual with LT4 Engine

[travislambert]

I recently dropped an LT4 GM crate engine (19332621) into my 2016 Camaro 2SS manual and I am having trouble coming up with a suitable tune.
My plan was to reference tunes from the 2016 Corvette Z06 and the 2016 Cadillac CTS-V which both have the LT4 engine and use the same ECM hardware.
The problem I'm having I believe is due to the combination of the Camaro, Corvette, and CTS-V operating systems all being different as well as some wiring differences/new sensors on the LT4 that were not present on the LT1.

The symptoms include:
P0101 - Mass or Volume Air Flow A Circuit Range/Performance
P0106 - Manifold Absolute Pressure/BARO Sensor Range/Performance
P1101 - Mass Air Flow Sensor Out of Self-Test Range
P2227 - Barometric Pressure (BARO) Sensor Circuit Range/Performance Problem

I think whats going on is that Ive wired these sensors to match the new 2017 Camaro ZL1, which happens to also match the Z06 and CTS-V that I'm referencing, but the Camaro operating system doesn't adapt.
Here's what I've changed with the wiring. (Notation: X1,X2 are the harness connections. #XXX are wire numbers.)

X1:
#4, #5 - Signal and reference wires from Throttle Inlet (Airbox) moved to Supercharger Inlet Air Pressure signal and reference
#13 - Wire added for Induction Air Temperature Sensor 2 signal which is used by the primary temperature and pressure sensor
#20 - Wire added for Super Charger Inlet Air Pressure Sensor Low Reference

X2:
#43, #44, #63 - Moved signal, 5V reference, and low reference wires used for primary MAP (These wires didn't really change, the physical location on the engine simply changes to wire to the primary pressure sensor on the back of the engine.)
#71 - Control wire added for SC Bypass Control (This wire provides ground whenever the bypass control should open)
#45, #64 - Signal and 5V Reference wires added for the Throttle Inlet Absolute Pressure Signal (Airbox)

So, just for kicks I loaded the Z06 OS with non-engine parameters from the Camaro and the new OS seems to be okay with the wiring. Everything engine related mostly works fine with the exception of the MAP sensor code P0106 - Manifold Absolute Pressure/BARO Sensor Range/Performance. The default Map sensor settings for the Z06 and CTS-V are: Linear 425.00 kPa, Offset -32.50 kPa. These values seem wrong for the Bosch MAP sensor 0 261 230 042, which I believe is a 2.5 bar sensor. I'm sure there's a good reason for this factory setting, but it doesn't seem to match the sensor. As a test, I changed the values to Linear 270.59 kPa, Offset -164. This got rid of the code, but the SC bypass seems to pretty much stay open all of the time.

Anyway, I cant use the Z06 OS because it causes way too many other problems like the gear indicator showing a 7 when its in reverse, the magnetic ride control modes wont change, etc., etc. So until the 2017 ZL1 OS is available, I need to figure out a way to get the Camaro SS OS to function even though the wiring is slightly different than what its expecting. I thought about trying the CTS-V OS, but since those only come in an Automatic and have a TCM component I figured I would just end up having different problems.

100 2016 Camaro OS with CTS-Z06 Mix.hpt
100 2016 Camaro OS with CTS-Z06 Mix.hpl
2016 Camaro 2SS Stock.hpt
2016 Corvette Z06.hpt
2016 CTS V Stock.hpt

[Redline MS]

I recently dropped an LT4 GM crate engine (19332621) into my 2016 Camaro 2SS manual and I am having trouble coming up with a suitable tune.
My plan was to reference tunes from the 2016 Corvette Z06 and the 2016 Cadillac CTS-V which both have the LT4 engine and use the same ECM hardware.
The problem I'm having I believe is due to the combination of the Camaro, Corvette, and CTS-V operating systems all being different as well as some wiring differences/new sensors on the LT4 that were not present on the LT1.

The symptoms include:
P0101 - Mass or Volume Air Flow A Circuit Range/Performance
P0106 - Manifold Absolute Pressure/BARO Sensor Range/Performance
P1101 - Mass Air Flow Sensor Out of Self-Test Range
P2227 - Barometric Pressure (BARO) Sensor Circuit Range/Performance Problem

I think whats going on is that Ive wired these sensors to match the new 2017 Camaro ZL1, which happens to also match the Z06 and CTS-V that I'm referencing, but the Camaro operating system doesn't adapt.
Here's what I've changed with the wiring. (Notation: X1,X2 are the harness connections. #XXX are wire numbers.)

X1:
#4, #5 - Signal and reference wires from Throttle Inlet (Airbox) moved to Supercharger Inlet Air Pressure signal and reference
#13 - Wire added for Induction Air Temperature Sensor 2 signal which is used by the primary temperature and pressure sensor
#20 - Wire added for Super Charger Inlet Air Pressure Sensor Low Reference

X2:
#43, #44, #63 - Moved signal, 5V reference, and low reference wires used for primary MAP (These wires didn't really change, the physical location on the engine simply changes to wire to the primary pressure sensor on the back of the engine.)
#71 - Control wire added for SC Bypass Control (This wire provides ground whenever the bypass control should open)
#45, #64 - Signal and 5V Reference wires added for the Throttle Inlet Absolute Pressure Signal (Airbox)

So, just for kicks I loaded the Z06 OS with non-engine parameters from the Camaro and the new OS seems to be okay with the wiring. Everything engine related mostly works fine with the exception of the MAP sensor code P0106 - Manifold Absolute Pressure/BARO Sensor Range/Performance. The default Map sensor settings for the Z06 and CTS-V are: Linear 425.00 kPa, Offset -32.50 kPa. These values seem wrong for the Bosch MAP sensor 0 261 230 042, which I believe is a 2.5 bar sensor. I'm sure there's a good reason for this factory setting, but it doesn't seem to match the sensor. As a test, I changed the values to Linear 270.59 kPa, Offset -164. This got rid of the code, but the SC bypass seems to pretty much stay open all of the time.

Anyway, I cant use the Z06 OS because it causes way too many other problems like the gear indicator showing a 7 when its in reverse, the magnetic ride control modes wont change, etc., etc. So until the 2017 ZL1 OS is available, I need to figure out a way to get the Camaro SS OS to function even though the wiring is slightly different than what its expecting. I thought about trying the CTS-V OS, but since those only come in an Automatic and have a TCM component I figured I would just end up having different problems.

100 2016 Camaro OS with CTS-Z06 Mix.hpt
100 2016 Camaro OS with CTS-Z06 Mix.hpl
2016 Camaro 2SS Stock.hpt
2016 Corvette Z06.hpt
2016 CTS V Stock.hpt

you can forget trying to follow the path of the LT4 OS.....its WAY more complicated then you think and there are significant pieces of logic in the OS you can't see. Your better off treating it like a E force swap on the base car. This will require some diagnostics to be turned off and go fix the MAF, VE and various other limits to resolve the higher airflow.....or should have waited for the ZL1!

[travislambert]

You're absolutely right about the LT4 OS. That was a dead end for sure. I went back to the Camaro OS and I have the tune much closer now.

The primary problem was the MAP sensor configuration was wrong. Once I fixed that other pieces just fell into place. It's certainly driveable now, but it still has a few gremlins to flush out during WOT.

Here's the latest of what I have in case anyone would like to provide advice. (This is the first car I've tried to tune.)

103 2016 Camaro OS with CTS-Z06 Mix.hpl
103 2016 Camaro OS with CTS-Z06 Mix.hpt

As for waiting for the ZL1, this may sound petty, but I really hate the suede interior. That on top of the dealer markups, the wait for production, etc. is what made me decide to go ahead and build my own.

[travislambert]

I'm making progress every day. Here's the latest I've tested, but I've since made some changes to disable diagnostics to avoid P0121.

108 Test Drive.hpl
108 2016 Camaro with LT4 Engine.hpt

I've been working to get the correct settings for the MAF. I'm still using the stock airbox and MAF so my thinking was that I could pull the frequencies from the connect and cruise tune and simply interpolate airflow values using my stock LT1 MAF configuration. The attached tune contains these interpolated values, but I was unsure about the value of 9,126.7 @15,000 Hz. This value is present in the stock LT1 tune immediately after the value 2,855.0 @ 8,550 Hz. Does anyone know if the 9,126.7 value @ 15,000 Hz is along the actual trend line of the sensor and the stock LT1 airbox? Obviously I won't be flowing that much air, but if this number is bogus then all of my values above 8,550 Hz will be off as well. Also, is my logic sound here for doing a simple interpolation?

Does anyone know why the tune is so sensitive around the Airflow->Throttle Area Limits->Max Area setting? Every stock LT4 tune I have (CTS-V, Z06, connect and cruise) has a value around 5,074.6 millimeters squared. The stock LT1 Camaro value is 4,703.9. I think it's the same throttle body on the LT1 and LT4, so I don't know why the settings are different and I don't know why I am unable to set the setting any higher without my long-term fuel trims going to approximately -10.

The tune I am testing with is almost verbatim engine wise to the connect and cruise and Z06 tune, but I haven't achieved a tune to get anywhere near the advertised horsepower. I'm assuming the stock settings work, so I'm thinking it has to be because of one of the custom settings I have.

[travislambert]

Here's where I'm at with my tune:

109 2016 Camaro SS LT4.hpt
109 Timing Pull At High Torque.hpl
109 Short Drive.hpl

It's running WAY too rich and pulling timing. Here's what I think is happening.

The Mass Airflow Sensor goes into the state of "MAP TPS Failed". From this point it basically goes into a limp-mode, though not technically a limp-mode.


Once it's in "MAP TPS Failed":
- The Airflow -> Electronic Throttle - > Pressure Ratio Limits are applied.
- The Airflow -> Dynamic - > Dynamic Airflow -> MAF Airmass Filt is applied.
- The Spark -> Advance -> (Main Spark Advance) Low Octane table gets used for timing instead of the High Octane table which pretty much kills all power.


I think if I could figure out what's causing the MAF state of "MAP TPS Failed" state, I think I'd be a lot closer to running correctly.


I thought about pulling back the MAF Airflow vs. Frequency until the car was no longer running rich, but I just hate to hack the MAF if the problem is something else. I know I could also copy the High Octane table over the Low Octane table, but I feel like that only masks the problem.

If you have a suggestion please share it. I've really been struggling.

[Ben Charles]

Quit "copying" stuff and just tune the rig....

[rjw]

Quit "copying" stuff and just tune the rig....

what he said....!!

[travislambert]

Quit "copying" stuff and just tune the rig....

I appreciate what you're saying, but that doesn't really help to answer my questions nor does it explain why a stock connect and cruise tune won't make the car at least run reasonably well with a few minor tweaks.


I get that copying values isn't optimal, but I hate deviate from the stock tune by too much. Custom tunes often involve disabling Displacement on Demand and months of drivability tweaking. For me I don't care about squeezing every ounce of power out of it. I want stock LT4 performance, drivability, fuel economy, and reliability. I don't understand why a stock tune won't get me there.


I've made adjustments to dial in the MAF where my LT fuel trims are mostly 0's across the board. I've also had to tweak the MAP sensor configuration to match the MAP sensor. I've verified the low end of the MAP configuration by comparing to the barometric pressure before startup. As a second check I also verified that value against a barometric pressure table for my elevation. Everything checks out, but on the high end I have no way to validate the MAP reading. At high RPM, I'm seeing a little over 10psi above barometric which I think exceeds the documented boost level for the supercharger. Can anyone explain this?


I now have the 'MAP TPS Failed' solved. That was either a bug in HP tuners or at least non-intuitive functionality. So I've had the P0101, P0106, P0121 checks disabled under Engine Diag -> Airflow for several iterations of testing. However, these setting weren't being pushed to the ECM when I would write the configuration only. I had to choose write entire to get it to work. I've since discovered that everything I've configured under Engine Diag doesn't seem to take effect until I 'write entire'. This seems like an HP tuners bug to me, but maybe it's something with the E92 ECM.


Now that the 'MAP TPS Failed' mystery is solved, I'm chasing down a problem related to Knock Retard. My car seems to be running from the low-octane tables. I've never put anything other than 93 octane gas in the car, and I don't hear the engine knocking, but the knock sensors are active which I'm pretty sure is the primary factor in the timing being pulled. I replaced the Low-Octane table with the High Octane table, graphed the Cylinder Airmass vs the Engine RPM, and went for a short drive. There's a lot of knock being reported.


Here's my latest 2 tests.


118 Knock Test.hpl
118 2016 Camaro SS LT4.hpt
117 Knock Test.hpl
117 2016 Camaro SS LT4.hpt


I'm not interested in throwing out the stock tune and starting over from scratch unless someone can explain technically why it'll never work. There has to be a logical explanation for why what I have isn't working.


I'd certainly be willing to pay for a professional tuner with Gen V LT4 experience to give me a hand.

[rjw]

some of the heavy hitters are not around, so be patient

I'm pretty green so don't listen to me

questions:

1)in that I can't see your dtc's, which ones are still present and what did you change/disable?

2) you don't have a wideband, so can't tell what your true afr's are?

3) are your knock sensor parameters the same as on the tune for your original engine

4) you're getting some burst knock, but some from unkown sources. search and log ALL sources of retard

5) I'm not seeing any values for maf hertz error in the scan?? if maf is not reading properly, you might be toast above 4k

I would at least invest in a wideband. if ALL the sensors are hooked up and reading properly, you could get away with a maf only tune (possibly)

what's with no engine dtc's showing up??

your car doesn't have an E92 ecm,or what?

[ABADZL1]

Well, you did say you would be willing to pay a tuner for help.
admperformance has a kit to do exactly what you have done with this car. Why don't you give Andy a call and pick his brain? Maybe he will tell you how they do it.

[travislambert]

Well, you did say you would be willing to pay a tuner for help.
admperformance has a kit to do exactly what you have done with this car. Why don't you give Andy a call and pick his brain? Maybe he will tell you how they do it.

That's actually where I got my engine and a few other conversion parts. Andy is a very knowledgeable guy, but unfortunately he hasn’t had a customer yet for the full LT1 to LT4 swap for a 2016 Camaro. I believe I’m his first customer for this package, but I did my own installation so he didn’t get the opportunity to tune the car.
He’s given me some helpful advice along the way and a tune he did for an LT1 with an LT4 supercharger, but the tune for a true LT4 is quite a bit different. He’s a very busy guy and from talking with him I don’t think he too interested in providing a lot of remote tuning help. There is no doubt that he’d be able to tune it with the car in his shop.

[Redline MS]

Quit "copying" stuff and just tune the rig....

Agreed.... You could have been done already

[travislambert]

some of the heavy hitters are not around, so be patient

I'm pretty green so don't listen to me

questions:

1)in that I can't see your dtc's, which ones are still present and what did you change/disable?

2) you don't have a wideband, so can't tell what your true afr's are?

3) are your knock sensor parameters the same as on the tune for your original engine

4) you're getting some burst knock, but some from unkown sources. search and log ALL sources of retard

5) I'm not seeing any values for maf hertz error in the scan?? if maf is not reading properly, you might be toast above 4k

I would at least invest in a wideband. if ALL the sensors are hooked up and reading properly, you could get away with a maf only tune (possibly)

what's with no engine dtc's showing up??

your car doesn't have an E92 ecm,or what?

Thanks for the questions. It's nice to see some level of interest in my post.

Here ya go:

1) There are no current DTCs. My diagnostic configuration is mostly the same as the stock LT1, but I do have P2101, P0101, P0106, P0121 disabled. I've adjusted the tolerances for MAF Fail High, Airflow Correlation, and Misfire detection to match the stock LT4 configs I have.

2) I have a friend coming with a wideband to help me tomorrow. I expect this will help a lot. Up until this point I've only had steady state fuel trims to look at.

3) I've tried knock sensor settings from a stock 2016 Z06, CTS-V, and connect and cruise tune. I was uncertain about trying settings from the LT1. I can see the LT1 knock sensor level multipliers are higher, which if I'm understanding correctly means they're less sensitive. In the back of my mind though I keep thinking the problem is likely somewhere other than the knock sensor settings though.

4) I noticed the burst knock too, but if I'm understanding it correctly the portion of burst knock is negligible. Please let me know if you think there is more digging I should do here.

5) I didn't know about that PID so I wasn't logging it. I think the MAF sensor is reading correctly, but I'll certainly add this on the next run. Thanks!

"what's with no engine dtc's showing up?? your car doesn't have an E92 ecm,or what?"
My car is without a doubt an E92.

[travislambert]

Agreed.... You could have been done already

Maybe you could have, but I probably couldn't. I'm new at this so I'm being very careful with every change as I know there is a lot I need to learn. I created this thread to get help with making a stock tune work with minimal changes. I'd like technical feedback on why the approach simply can't work or suggestions on how to make it work. I appreciate your suggestion, but there should be a way to adapt the stock tune. I have the tune file for a 2016 CTS-V which is pretty much identical as far as the engine goes to a 2016 Camaro with an LT4... The engine, exhaust manifolds, airbox, etc. are all identical to what I'm using. I can't help but think I'm really close to everything falling into place. At some point I may have to take it and have a custom dyno tune done, but that isn't my goal. I don't have a good way to haul the car and the closest shops to me are over a 100 miles away. If at all possible I wan't to make the stock tune work or figure out why it's a dead end approach.

[rjw]

Thanks for the questions. It's nice to see some level of interest in my post.

Here ya go:

1) There are no current DTCs. My diagnostic configuration is mostly the same as the stock LT1, but I do have P2101, P0101, P0106, P0121 disabled. I've adjusted the tolerances for MAF Fail High, Airflow Correlation, and Misfire detection to match the stock LT4 configs I have.

2) I have a friend coming with a wideband to help me tomorrow. I expect this will help a lot. Up until this point I've only had steady state fuel trims to look at.

3) I've tried knock sensor settings from a stock 2016 Z06, CTS-V, and connect and cruise tune. I was uncertain about trying settings from the LT1. I can see the LT1 knock sensor level multipliers are higher, which if I'm understanding correctly means they're less sensitive. In the back of my mind though I keep thinking the problem is likely somewhere other than the knock sensor settings though.

4) I noticed the burst knock too, but if I'm understanding it correctly the portion of burst knock is negligible. Please let me know if you think there is more digging I should do here.

5) I didn't know about that PID so I wasn't logging it. I think the MAF sensor is reading correctly, but I'll certainly add this on the next run. Thanks!

"what's with no engine dtc's showing up?? your car doesn't have an E92 ecm,or what?"
My car is without a doubt an E92.

why do you have all those dtc's ignored?

I have an lt4 cam in my son's 5.3L Silverado and I am using the 5.3L knock sensor settings. if you have for example a maf error, which you do, things won't work great. I am tole that E92's might not like having sensors missing...you have maf, map and tps errors that are being ignored. Did the engine come with it's own maf? or are you using yours from the lt1

in other words, is the maf , tb and map all new and came with the lt4?

several ways to go about things, but logging as many knock related pids as possible should get you to the causes

good luck with it

edit:

I know that the lt4 has an extra iat sensor,plus a bunch of stuff related to the sc parameters......

for example under Engine-> Airflow->General-> Map-> sensor config->the lt4 is set to sc-sciap-tiap..which if you do not have the second iat just before the tb, that alone should cause problems

Others have said it, but maybe you should try to tune it as a non-lt4, in that there sensors that you might not have

not that hard to do, I think

[travislambert]

why do you have all those dtc's ignored?

I have an lt4 cam in my son's 5.3L Silverado and I am using the 5.3L knock sensor settings. if you have for example a maf error, which you do, things won't work great. I am tole that E92's might not like having sensors missing...you have maf, map and tps errors that are being ignored. Did the engine come with it's own maf? or are you using yours from the lt1

in other words, is the maf , tb and map all new and came with the lt4?

several ways to go about things, but logging as many knock related pids as possible should get you to the causes

good luck with it

edit:

I know that the lt4 has an extra iat sensor,plus a bunch of stuff related to the sc parameters......

for example under Engine-> Airflow->General-> Map-> sensor config->the lt4 is set to sc-sciap-tiap..which if you do not have the second iat just before the tb, that alone should cause problems

Others have said it, but maybe you should try to tune it as a non-lt4, in that there sensors that you might not have

not that hard to do, I think

"why do you have all those dtc's ignored?"
That's certainly a fair question. The LT1 with LT4 supercharger tune I have from ADM performance has them ignored. Since I was seeing the DTCs relating to the same errors I decided to do exactly what Andy did and ignore the error. I wish I had a better answer for you. I'd like to not have to ignore these errors.

"Did the engine come with it's own maf? or are you using yours from the lt1"
I'm using the MAF (and matching airbox) from the LT1. I started with the stock LT1 MAF config, but later lowered the values to 90% of the originals to get the fuel trims a little closer.

"for example under Engine-> Airflow->General-> Map-> sensor config->the lt4 is set to sc-sciap-tiap..which if you do not have the second iat just before the tb, that alone should cause problems"
You're absolutely right, but I actually ran wiring for the new sciap and the IAT2. This all worked great with the Corvette OS, but then everything else with the car wouldn't work. The Camaro OS however would never pick up on the SCIAP (IAT2 worked fine). I ended up switching the sensor config to NA-TIAP which ignores the SCIAP. That seemed to make the Camaro OS a lot happier.

Thanks for your input.

[travislambert]

I just got back from a rather successful test run. I switched the settings under Spark to better match the CTS-V instead of the Z06/Connect & Cruise. The only deltas I borrowed from the Z06 were for spark smoothing. I also went with other CTS-V knock sensor configs, VE configs etc. It's still thinks it seeing a little knock, but nothing like before the changes. Of course the High and Low octane tables are back in stock configurations, so it's stepping down the timing to avoid knock as it senses what it thinks is knock. Obviously there won't be as much knock, but before it was pulling so much timing there wasn't any power either. It seemed like the power was mostly there tonight.

I think what I have should serve as a good basis for minor tweaking at this point. Hopefully with a little wideband tuning tomorrow I'll have it in pretty good shape, but please don't let this small bit of success deter you from providing feedback or asking questions. There's still lots of room for improvement.

Here are the files.

120 Test Run.hpl
120 2016 Camaro SS LT4.hpt

[rjw]

no time to look at tunes/logs, but (because of weight of vehicle, my truck vs vette) I had a lot of surging and knock at low r's (like your low load knock)

I wouild put the knock sensors to same settings as on your lt1 as a test.

also, go to the camshaft timing tables (engine-airflow-variable cam-base) and put everything below 4k to zero. low ,med and high.put in a conservative timing table in high and copy to low. by conservative, I mean 12 in boost. also log intake cam angle, to see if it is moving...there's more, but start there. also, you MUST have a reading for maf hertz.

you could do a quick maf only tune if you can get a reading. make sure your maf settings are for your MAF, not the vette. check that column values are for your car, not the vette

EDIT: make sure that your cc size for the lt1 tb is correct.... the ecm needs to learn the tb opening (maybe). I put an lt1 tb on a 5.3L and idle at first was rough. I found that with key on engine off, I pressed the pedal a bunch of time to the floor and release...things were happier afterwards. if scanning you can log accel pedal position to check pedal only

[travislambert]

no time to look at tunes/logs, but (because of weight of vehicle, my truck vs vette) I had a lot of surging and knock at low r's (like your low load knock)

I wouild put the knock sensors to same settings as on your lt1 as a test.

also, go to the camshaft timing tables (engine-airflow-variable cam-base) and put everything below 4k to zero. low ,med and high.put in a conservative timing table in high and copy to low. by conservative, I mean 12 in boost. also log intake cam angle, to see if it is moving...there's more, but start there. also, you MUST have a reading for maf hertz.

you could do a quick maf only tune if you can get a reading. make sure your maf settings are for your MAF, not the vette. check that column values are for your car, not the vette

EDIT: make sure that your cc size for the lt1 tb is correct.... the ecm needs to learn the tb opening (maybe). I put an lt1 tb on a 5.3L and idle at first was rough. I found that with key on engine off, I pressed the pedal a bunch of time to the floor and release...things were happier afterwards. if scanning you can log accel pedal position to check pedal only

Thanks for the suggestions.

My MAF settings are certainly based on my original Camaro LT1 tune. I did lower the settings to 90% of the originals to get the LT fuel trims to settle on 0, but since then I've made other changes and it's probably time to put those back to stock.

Your throttle body comment certainly has my interest. That's been a question that I've had because the stock tunes I've been referencing have different settings for the same engine/TB and I'm not sure why.

2016 CTS-V = 4,470.0 mm2

2016 Z06 = 5,074.6 mm2

2016 Connect and Cruise ECM = 5,074.6 mm2

2016 Camaro SS with LT1 = 4,703.9 mm2

I believe the LT1 and LT4 use the same TB so shouldn't the values be the same? The connect and cruise and CTS-v tunes certainly target the same engine. Does anyone know why the settings are different?

I'm currently using the Camaro TB maximum area. This change was made at the same time as the MAF config changes to get my long term fuel trims to zero. Are the stock MAF settings reliable, or are those potentially hacked a little by GM while tuning? Because like the TB area, the MAF sensor and airbox I believe are the same on the CTS-V as the Camaro SS (I need to fact check this, but I believe this to be true.). However, like the TB area tunes, the tunes for MAF are also different between the Camaro and CTS-V. I'm guessing they've just been tweaked off of actual for something downstream, but I don't know??

[rjw]

you need to set the area of the tb to match YOUR CAR with the LT1

so, once you have the maf and tb settings from YOUR LT1, not the vette, try to see if you can get a few of those dtc's back to unbypassed.

at that point, the car could run strange, because the vve and maf could be way off

if you get the maf working and a wideband, you can log the error, set maf down to a low rpm and run on maf only, till you get the vve tweaked