Thread: Let's just rename this PurpleGuy's GTO tuning endeavor

I dunno if Scotty has a FB. Cam deactived his years ago lol

Also to add I have DFCO disabled, cat overtemp protect disabled, o2's disabled, and dynamic airflow doesn't look to be enabled in the factory tune. The high RPM disable is 300 and the high rpm re-enable is 200. So it shouldn't ever go to dynamic airlfow

The computer has been touched before if the dynamic airflow settings are that low. Stock settings are 4,000/3,900rpm.

Go to the advanced reply box and click the attachements icon that looks like a paperclip. Then add the tune and logs from there.

One is for sure though, if the those injectors has a different flow rate you should do that math and tell the computer. Don't just scale the fueling, make sure it at least knows the flow rate.

Well that's interesting. Okay I have three files here. This one is the tune as I found it. Stock 2006 GTO Auto.hpt

This one is where I'm currently at. I've made 8 revisions to the MAF curves so farGTO MAF STEP 8.hpt

And here is the log where the car hiccuped and then went way rich. Looking back at the log now I just noticed it went lean for a split second and that must've been the hiccup. Then it went way rich. The hiccup is at the very end of the log. GTO LOG.hpl

I will do some looking and figure out the flowrate of these injectors. I'm assuming I'll have to redo the MAF curve after that correct?

EDIT: Multiple people saying stock LS2 injectors are 32lb. ZZP and several others saying the L32 injectors are 33lb.

This issue is definitely something from what I've been changing, just don't know what. It hasn't done this until I started playing with the tune and I've been close to WOT up to about 100mph with no issues what so ever before working on the tune. Just doesn't make sense cause the only thing I've actually done is scale the MAF table so it's not pig rich.

You left the rear o2 sensor test and the cat test on in the engine diag tab. That could cause a sudden change in fueling if the test gets enabled. Those must be disabled. See if that helps.

Also your cylinder volume is for a 5.7 engine. Didn't you say this was a 6.0? I think the correct cylinder volume is like .74594 or something from a 6.0 engine size.

Yes, the MAF/VE may need minor changes once the injector flow rate is corrected.

Okay, I would think having the rear 02's disabled would keep the tests from running but never know I guess.

And yes it is a 6.0. Not sure why it's under a 5.7. I don't think the 5.7 cars even use this same ECM so I'm not sure why it's set like that. Didn't even look at that honestly. Pretty obvious someone has been in here before me apparently between the wrong engine size and the dynamic air being turned off.

I'll get those tests disabled and correct the injector size but it's raining now so I'm probably not going to do anymore logs today.

I've found a couple threads where guys says the cylinder volume doesn't matter on this. I'll change it anyway to be safe.

2005 LS2 cylinder volume

Cam did you see anything that stood out in that log?

I always changed it just in case I guess. For sure on the P01/P59 it matters, that number is used for all calculations on those.

The logs looks okay for just normal driving. The timing does kinda bottom out when you are going at slow speeds. In the Idle Adaptive spark control you may be able to cut the under/over speed spark correction tables back some to see if that makes it less. Right now there is a very big spread in what the tables are allowed to do. On camshaft swaps I tend to cut the tables back. So instead of +13 and -20 degrees of timing, it's +/- 10 for each. If you click on the tables you'll see what I'm talking about.

Okay I can do that. Hopefully disabling those tests will prevent the hiccup again.

Cam what are you referring to on the P01/P59?

Also the injector rate is already set to 33lbs it looks like under flow rate vs KPA.

Originally Posted by PurpleGuy

Cam what are you referring to on the P01/P59?

Also the injector rate is already set to 33lbs it looks like under flow rate vs KPA.

those are different pcms models.

Ahh gotcha. Looking back through I also didn't disable LTFT. I should probably disable LTFT as well shouldn't I?

For wideband tuning you'd need to have closed loop disabled, long term fuel trims and if the computer has it, the short term fuel trim disable.

Those things can also be turned off with the scanner and same with trim reset.

Okay I have closed loop and LTFT disabled. Didn't see any STFT stuff in there. Going to try getting some more logs done tonight as long as the rain stays away. Been rainy and gloomy the last 3 days.

No dice. Still doing the same thing. Did it twice. Exact same scenario as last time. Hiccupped and went stupid rich. Both times it did this it threw a P0101 for the MAF. Was able to clear the code and it comes right back to stoich. I pulled the MAF off. It visually looks fine. I see no dirt or debris on the elements or the screen. Don't know if the MAF is on the way out or what. It hasn't done this until I started tuning. If I knew there'd be no adverse effects I'd set the code to not report and see what it does.

Doing some reading and found this info. DTC P0101 Mass Air Flow (MAF) Sensor Performance

Under "conditions for setting the DTC" it says MAF frequency is 50% off from the SD calculation. Wonder if maybe this is my problem.

Under "Actions taken when set" it says the PCM goes to SD which seems to be what my car is doing and that's why it's so rich cause I haven't touched the SD tables yet.

More reading. Apparently I'm not the only one that's had this issue with the P0101 code. Sounds like it is a rationality issue between the MAF and VE tables not being similar.

This thread here says to increase the airflow delta to correct this as it will broaden the range before the code will set and put the car into SD. P101 - Max Delta Airflow

I see it as I have four options. First one is set the code to not report. Might keep it from going into SD even if the rationality is incorrect. Option 2 change the delta table. Option 3. I can set the min coolant temp too high to run the test. Or Option 4 I can stop the MAF where I'm at and do some SD tuning to get the tables closer to each other and that should keep them rational and keep it from setting the code?

Thoughts? I'm all ears. I won't lie in that I'm very new to this

Figured I'd update this. Drove the car quite a bit this summer. Put over 5K miles on it and had 0 issues with it so not much to update on in terms of problems. Got new Pedder's springs and Delco shocks in the back to fix the ass sag-apparently I didn't think any pictures of that. Will get better shocks later

Got the MAF and speed density tuning done on it and the car drives great I think. Averaged close to 20mpg going back and forth to work

Buddy of mine gave me a set of TRS HID's for free. I did buy a set of headlights that are almost brand new but those are not in yet. Waiting to put those in until these are bad enough. GTO headlights are NOT cheap at all so I gave these a good buff. I may try to retro these and see what I can do with them.



Tinted the windows myself. Back window sucked ass getting the old tint off which was no surprise at all. Other windows were pretty easy. Back window turned out like ass when I was done too lol. Rest of the windows came out fine. I was quoted over 400 bucks to remove and retint, no thanks.



Both of the subs in the deck were junk and a couple other speakers were junk. Replaced the entire stereo. Nice Kenwood touchscreen to replace the Pioneer that was in it. Decent speakers but nothing crazy at all. I had right at 100 bucks into 4 new speakers and less than 200 bucks into replacing the subs in the back deck. Just wanted some decent tunes. No pics again apparently. I'm getting pretty bad about that


Ahh let see, I did buy some more go fast parts which is much more exciting and important.

AFR 245 heads. 65cc chamber so comp should stay the same. I did also buy a NW102 throttle body but that hasn't show up yet. Going to do a Fast 102 and that will wrap up the induction side of things.



Vararam intake I got cheap. May not end up using this but we'll see




One issue I have had is the header hitting the steering shaft again even after new mounts. I made some shims to push the engine up and it did help but still doing it. Thinking that header is going to get the hammer treatment at some point. Can't say it's poor header fitment since they're cheap cause even some of the Kook's headers do this too and they're spendy so idk lol.




That's about it, car is away for the year.




Don't really have any plans for next year. It probably won't get driven as much I will say that. I want it to stay nice. I do think I'm going to replace the cam at some point. I like the cam that's in it and it's great for driving everyday but I want to go bigger since I won't drive the car as much. Also want to take advantage of those awesome flow numbers the AFR heads provide. Long term goal is probably a Procharger or turbo so something that will work good with that.

Oh and a little burnout lol
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