(okay, just a joke; but the truth is the cam specs don't see all that radical)
Rough Idle
Thread Starter
Melting Slicks
Joined: Apr 2004
Posts: 2,775
Likes: 138
From: cyberspace NY
Rough Idle
5,500 miles. 2017 LT1 GS.
The idle is slightly rough. I can feel it in my seat, and the passenger can also feel in the the seat of their pants.
Any Ideas ?
Still runs fine all the way to 6,000 RPM. Ran it at the track, runs amazing.
What would cause a very slight idle roughness ?
The idle is slightly rough. I can feel it in my seat, and the passenger can also feel in the the seat of their pants.
Any Ideas ?
Still runs fine all the way to 6,000 RPM. Ran it at the track, runs amazing.
What would cause a very slight idle roughness ?
Intermediate
Joined: May 2018
Posts: 34
Likes: 10
From: Westfield Mass
my 2017 stingray does the same thing its normal and just the way the engine is some would refer to it as camshaft lope LSA (lobe separation angle) determines the choppiness, it has to do with the overlap of when both valves are open, as in when the exhaust valve is closing and the intake valve is opening to pull fresh fuel in on the intake stroke after pushing out the burnt fuel.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
I don't believe it is the cam either-[-It is just not lopey to me at all or rough idling
My suggestion would be to take it to a tuner---that can data log certain items OR even to any shop that has a TECH II device or something similar
1st List all or any of the mods you have installed
Most likely culprits are LTFT fuel trims that have become way off --usually due to a CAI or aftermarket exhaust or LT headers
Also have any shop do an "IDLE RELEARN PROCEDURE "
Make sure your LTFT fuel trims are "0" or slightly negative----Never positive
That can only be corrected with a tuning device using your MAF table
While there also have a tuner raise the "Warmed idle" from 650 to 700 RPM's--this will also smooth the idle greatly
My suggestion would be to take it to a tuner---that can data log certain items OR even to any shop that has a TECH II device or something similar
1st List all or any of the mods you have installed
Most likely culprits are LTFT fuel trims that have become way off --usually due to a CAI or aftermarket exhaust or LT headers
Also have any shop do an "IDLE RELEARN PROCEDURE "
Make sure your LTFT fuel trims are "0" or slightly negative----Never positive
That can only be corrected with a tuning device using your MAF table
While there also have a tuner raise the "Warmed idle" from 650 to 700 RPM's--this will also smooth the idle greatly
Le Mans Master
Joined: Oct 2014
Posts: 8,673
Likes: 2,728
From: Atlanta GA
They all idle a little bit rough; I have GDS2 and HP Tuners ... and see absolutely nothing wrong but mine does not idle smooth, its not Lopey like a big cam, just a little bit rough at idle , my C6 was the same way , its not going to idle like a Ford Taruis 
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Cruising
Joined: Jul 2022
Posts: 13
Likes: 4
From: San Antonio, TX
I was wondering about that.
Having come from 2019 & 2021 Camaros with the same engine, they never idled this rough so consistently. There have been times I expected a CEL. I was beginning to wonder if someone had loaded a tune in it, especially since my skip shift is missing, completely.
Having come from 2019 & 2021 Camaros with the same engine, they never idled this rough so consistently. There have been times I expected a CEL. I was beginning to wonder if someone had loaded a tune in it, especially since my skip shift is missing, completely.
Racer
Joined: May 2017
Posts: 495
Likes: 51
From: Woodlands Texas
I was wondering about that.
Having come from 2019 & 2021 Camaros with the same engine, they never idled this rough so consistently. There have been times I expected a CEL. I was beginning to wonder if someone had loaded a tune in it, especially since my skip shift is missing, completely.
Having come from 2019 & 2021 Camaros with the same engine, they never idled this rough so consistently. There have been times I expected a CEL. I was beginning to wonder if someone had loaded a tune in it, especially since my skip shift is missing, completely.
However if the idle was fine or not how it is now, check your plugs wires, and O2's. These GEN V are pretty sensitive to changes and have to be just right.
Le Mans Master
Joined: Oct 2014
Posts: 8,673
Likes: 2,728
From: Atlanta GA
