Stutter/Choppy on Acceleration

nmal · 03-25-2026, 06:48 PM

About 8 months ago I did FBO to my car with the following mods:
- Rotofab CAI
-Flex Fuel Kit
-LT5 95 MM TB
-LT2 IM
-Stainless Power LTH with high flow cats

The car drove fine for a while (or maybe I just never noticed it before) but a couple months after install I have a stutter when accelerating. When I give light throttle from anywhere from 1k-3k RPM, the acceleration stutters. Its hard to describe or get on video, but the best explanation I can think of is if you make a "vvvvvvvvvvvvv" sound and quickly shake your head up and down while making that sound, thats what the stutter sounds like. The acceleration is choppy and you can feel the car lurch forward and backwards as it stutters. This does not happen all the time, and when giving more throttle it seems to skip the stutter a majority of the time. The car has 30K miles and seems to idle fine.

I already replaced the spark plugs, and replaced one or two questionable plug wires. There is not one specific cylinder that misfires more than others on HP tuners, so I doubt it is a bad coil pack. Car is tuned by GPI so I doubt it is a bad tune either. I was thinking it could either be:
1. Bad/clogged injectors
2. Slight intake leak from under LT2 IM
3. Slight leak near exhaust clamps

The similar issues I've read on here have been bad injectors so that's what I'm leaning towards but I want to be pretty confident before I buy new injectors. Anyone have any thoughts?

ZLRob · 03-25-2026, 07:04 PM

Grab a log of the issue and throw it up on here. Any guesses is just pishposh right now.

Any sort of acceleration issues, however, are usually attributed to airflow issues, the throttle body being the first suspect assuming the calibration was went over properly. Vacuum leaks are always possible, but a little unlikely given how these engines are built and the gasket sets around them are designed to engage.

Injector failure at 30K is possible, but not super likely. Yeah, so again, a log here is going to be the best course of action.

nmal · 03-25-2026, 07:35 PM

Thanks,
Heres a log file I had of the issue
https://drive.google.com/drive/folde...L1?usp=sharing
The bucking occurs at about 17, 22, and 27:40 minutes into the log

03-25-2026, 06:48 PM	#1
nmal Drives: 2023 Rapid Blue 2ss Join Date: Oct 2022 Location: SoCal Posts: 44	Stutter/Choppy on Acceleration About 8 months ago I did FBO to my car with the following mods: - Rotofab CAI -Flex Fuel Kit -LT5 95 MM TB -LT2 IM -Stainless Power LTH with high flow cats The car drove fine for a while (or maybe I just never noticed it before) but a couple months after install I have a stutter when accelerating. When I give light throttle from anywhere from 1k-3k RPM, the acceleration stutters. Its hard to describe or get on video, but the best explanation I can think of is if you make a "vvvvvvvvvvvvv" sound and quickly shake your head up and down while making that sound, thats what the stutter sounds like. The acceleration is choppy and you can feel the car lurch forward and backwards as it stutters. This does not happen all the time, and when giving more throttle it seems to skip the stutter a majority of the time. The car has 30K miles and seems to idle fine. I already replaced the spark plugs, and replaced one or two questionable plug wires. There is not one specific cylinder that misfires more than others on HP tuners, so I doubt it is a bad coil pack. Car is tuned by GPI so I doubt it is a bad tune either. I was thinking it could either be: 1. Bad/clogged injectors 2. Slight intake leak from under LT2 IM 3. Slight leak near exhaust clamps The similar issues I've read on here have been bad injectors so that's what I'm leaning towards but I want to be pretty confident before I buy new injectors. Anyone have any thoughts?

03-25-2026, 07:04 PM	#2
ZLRob Super Stock Drives: Chevrolet Camaro ZL1 Join Date: May 2022 Location: Concordia Posts: 982	Grab a log of the issue and throw it up on here. Any guesses is just pishposh right now. Any sort of acceleration issues, however, are usually attributed to airflow issues, the throttle body being the first suspect assuming the calibration was went over properly. Vacuum leaks are always possible, but a little unlikely given how these engines are built and the gasket sets around them are designed to engage. Injector failure at 30K is possible, but not super likely. Yeah, so again, a log here is going to be the best course of action. __________________ 2017 Red Hot ZL1 A10 - Apex ARC-8's, 305/ 325 PS4's, DSX 9.06 12% lower, Griptec OE upper, NGK HR7 Ruthenium plugs, Nostrum 25+ injectors, XDI Goliath HPFP, Katech dual in tank LPFP, Katech oil pump, LME tensioner, DOD delete, LT1 big fuel cam, Jokerz ported blower, MPI lid, GMS hood extractor bracket, Granatelli SS plug wires, Cordes LTR reservoir, DMS T-stat housing, 186* LS3 T-stat, Borla X pipe, Black Widow Angry Housewife/ Corsa NPP mufflers, BMR engine mounts, Banks iDash, Lithium Battery, AEM X- Series, HP Tuners, E85, 16.5 psi 758 HP/ 804 TQ

03-25-2026, 07:35 PM	#3
nmal Drives: 2023 Rapid Blue 2ss Join Date: Oct 2022 Location: SoCal Posts: 44	Thanks, Heres a log file I had of the issue https://drive.google.com/drive/folde...L1?usp=sharing The bucking occurs at about 17, 22, and 27:40 minutes into the log

User Name		Remember Me?
Password