C7 idling question
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C7 idling question
I have had Corvettes long enough to know that the idling is supposed to rough and is absolutely normal. My warranty is about to expire and don't know if I am being OCD but today I noticed that the RPM in the tachometer during idling has a very slight up and down. Is this normal? I am not sure if I never paid attention before or it never did it before. Mine is an M7 Stingray.
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My tach stays steady but the idle is ****, been that way since new. My last two C6's when I had them also since new was the same way. I have had zero luck in the smooth idle department in Corvettes for the last ten years.
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My three C5s and now my C7 have all had a rough idle to them and when I had a dealer look at my first C5 for that issue, I was told it is normal. I have not noticed the tach fluctuating though.
Racer
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At normal operating temp in Drive or Park my tach is between 600 and 700 RPM. Watching it closely, it does move every now and then but it remains in this range. The movement isn't in sync with the rough idle though.
/JD
/JD
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Thanks for all the replies, the movement in the needle is very minor but it is there nonetheless. Performance seems normal and no MIL.
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These threads come up from time to time in C6 and C7 and what baffles me is how some members say they have a butter smooth idle when every motor is built to the exact same specs. I would love to feel what their interpretation is of a smooth idle in their car.
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Melting Slicks
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Ditto the rough idle but no noticeable RPM fluctuation...
Suggest hooking it up to an OBD analyzer to see what RPM is being seen by the engine.
I bought the Dash Command app on my iPad along with a VeePeak wireless OBDII scanner to see what the car's doing.
Suggest hooking it up to an OBD analyzer to see what RPM is being seen by the engine.
I bought the Dash Command app on my iPad along with a VeePeak wireless OBDII scanner to see what the car's doing.
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if I knew how to post a video here I would show you our 2001 Z06 with 135k idling smooth as silk !!!! as well as our 13 Z06
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Plug a scanner into it and see what the ECM says the RPM is. So if you see it running between say 1000 and 1500, you have a problem. OTOH if it is between 1000 and 1050, you are within norms. It will never stay at a certain RPM so there will be fluctuations. What we are trying to see is if there is a lot of difference or a smaller difference.
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I have had Corvettes long enough to know that the idling is supposed to rough and is absolutely normal. My warranty is about to expire and don't know if I am being OCD but today I noticed that the RPM in the tachometer during idling has a very slight up and down. Is this normal? I am not sure if I never paid attention before or it never did it before. Mine is an M7 Stingray.
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Once the C7 warms up, the idle smooths out. It's also smoother on 91/93 octane fuel. Which C- Series do you have ?
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2012 Base, 2013 GS so those were LS-3 motors. Currently 2019 GS. Always have run 93 octane. But forget about my cars, I have been in numerous other C6's and C7's and have never experienced a smooth idle.
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How do you SHOW me a car running smooth as silk. If I took a video of my car it would look to be running smooth also, unless your sitting in the seat and feel it.
Melting Slicks
Joined: Apr 2005
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the lump idle is a feature not a bug, it is a call back to the lumpy cams of yesteryear. slight fluctuations in the idle like you describe is probably normal. I would live with it until it causes a problem or take it to a dealer have them do the diagnostics and pay 175 bucks( in the past my dealer has waived that but I have been bringing both of my corvettes to them for 10years)
Drifting
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I got news dude, warranty or not, going into a dealer and saying "my tach fluctuates a little at idle" and expecting some sort of warranty repair would be like expecting Bernie Sanders and AOC
to co-sponsor a fiscal policy bill that actually makes a shred of sense and has a glimmer of hope of being sustainable
to co-sponsor a fiscal policy bill that actually makes a shred of sense and has a glimmer of hope of being sustainable
