Brand new stock/untuned ZL1 LTFT's very negative, normal?

SATINSTEEL1LE · 03-28-2022, 10:06 AM

Im trying to find out if I should be concerned with my new 21 ZL1 I just got. The Long term fuel trims are very negative which means the car is trying to undo a very rich condition that I assume the stock tune is calling for?? I dont have a wideband installed, so the log I have has limited info. Is this normal for a stock ZL1 a10??

wnta1ss · 03-28-2022, 12:13 PM

Seems weird. There was just a thread where a guy picked up his new ZL1 and it was getting VERY BAD mpg. He ended up unplugging the battery for a while to 'reset' the car. After he hooked it back up and drove some more, he said it acted MUCH better?

SATINSTEEL1LE · 03-28-2022, 05:35 PM

Quote:

Originally Posted by wnta1ss

Seems weird. There was just a thread where a guy picked up his new ZL1 and it was getting VERY BAD mpg. He ended up unplugging the battery for a while to 'reset' the car. After he hooked it back up and drove some more, he said it acted MUCH better?

Yeah I was the one that told him to do that. Lol. I’ve done that a few times and my gas mileage is completely fine. Im looking at fuel trims. This is probably the wrong forum to ask. I’ll take this to the HPTuners forums.

KingLT1 · 03-28-2022, 08:09 PM

-11% is not that rich. Very rich would be the point where the ECM can not correct. It's still able to correct afr to maintain stoich. I do agree it's odd that it's showing -11%. Most stock tunes are around 0 to +5%. Try resetting the fuel trims and see what happens.

JANNETTYRACING · 03-30-2022, 07:53 PM

Quote:

Originally Posted by SATINSTEEL1LE

Im trying to find out if I should be concerned with my new 21 ZL1 I just got. The Long term fuel trims are very negative which means the car is trying to undo a very rich condition that I assume the stock tune is calling for?? I dont have a wideband installed, so the log I have has limited info. Is this normal for a stock ZL1 a10??

I would expect to see this if you are using Non Ethanol fuels.

Ted.

SATINSTEEL1LE · 03-30-2022, 09:38 PM

Quote:

Originally Posted by JANNETTYRACING

I would expect to see this if you are using Non Ethanol fuels.

Ted.

Im not. Im using standard 93 from Shell.

Megahurtz · 05-08-2022, 07:50 AM

That isn't unusual at all

03-28-2022, 10:06 AM	#1
SATINSTEEL1LE Account Suspended Drives: 21 ZL1 Join Date: Feb 2022 Location: South East Posts: 662	Brand new stock/untuned ZL1 LTFT's very negative, normal? Im trying to find out if I should be concerned with my new 21 ZL1 I just got. The Long term fuel trims are very negative which means the car is trying to undo a very rich condition that I assume the stock tune is calling for?? I dont have a wideband installed, so the log I have has limited info. Is this normal for a stock ZL1 a10?? Attached Images

03-28-2022, 08:09 PM	#4
KingLT1 Drives: 2016 1SS NFG A8 Join Date: Aug 2017 Location: 46804 Posts: 6,786	-11% is not that rich. Very rich would be the point where the ECM can not correct. It's still able to correct afr to maintain stoich. I do agree it's odd that it's showing -11%. Most stock tunes are around 0 to +5%. Try resetting the fuel trims and see what happens. __________________ 2016 NFG 1SS A8 Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA

03-28-2022, 12:13 PM	#2
wnta1ss Drives: 2017 Camaro 1SS Join Date: Aug 2016 Location: NH Posts: 1,692	Seems weird. There was just a thread where a guy picked up his new ZL1 and it was getting VERY BAD mpg. He ended up unplugging the battery for a while to 'reset' the car. After he hooked it back up and drove some more, he said it acted MUCH better?

05-08-2022, 07:50 AM	#7
Megahurtz Snackbar Tuning Drives: 2023 SGM ZL1 Join Date: Oct 2016 Location: Florida Posts: 1,098	That isn't unusual at all

User Name		Remember Me?
Password