C7 rough idle
Melting Slicks
Joined: Oct 2004
Posts: 2,385
Likes: 160
From: Orlando FL
I had the same concern but my Corvette tech said it is normal behavior with this engine. I've also heard it is somewhat due to direct injection and/or cam profile. Just know it is not as smooth as my previous LS7 engine. But that's okay. It's a great Corvette!
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3rd Gear
Joined: Sep 2019
Posts: 3
Likes: 2
From: Bluffton, SC
Thanks much for the quick responses. It does not bother me at all unless it is not normal for this engine. It has been many years since my last Vette. Love this one and thanks again for your responses.
Team Owner
Joined: Aug 2007
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From: I live my life by 2 rules. 1) Never share everything you know. 2)
St. Jude Donor '11-'12-'13, '16-'17-'18
I must say my GS's idle does seem a bit more rough than it did before the cam/lifter replacements...
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First thing I noticed about my GS when I took it for a test ride with 2 miles on it. Salesman said it's normal for the car. At least it lets me know it;s alive. Not like the glass smoth idle of the 283 engine my father had when you didn't even know it was on.
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The Corvette has had a slightly rough idle all the way back to the C5. Unless it is excessive, it is normal.
Instructor
Joined: Aug 2019
Posts: 161
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From: USA
Is it sometimes more rough at idle than other times? Mine is. I put 20oz of Techron in the tank in case the fuel injectors aren’t spraying a fine enough mist. The rougher than normal idle happens so infrequently that I can’t tell if the Techron did anything yet. 2017 GS 11k miles.
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From: USA
Team Owner
Joined: Aug 2007
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From: I live my life by 2 rules. 1) Never share everything you know. 2)
St. Jude Donor '11-'12-'13, '16-'17-'18
I pretty much exclusively run either Shell V-Power or Chevron Supreme (that has Techron)
Last edited by KenHorse; Oct 3, 2019 at 12:01 PM.
Melting Slicks
Joined: Jul 2005
Posts: 2,060
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From: winter haven florida
St. Jude Donor '12
Mine was rough until I had it tuned. After my tune the idle is very smooth and all the part throttle bog and lag at lower rpms is gone. Car is night and day improved.
Melting Slicks
Joined: Dec 2017
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From: Central Commiefornia
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St. Jude Donor '11-'12-'13, '16-'17-'18