Is this bad?
02-04-2018, 09:41 AM
#1
Is this bad?
02/21/18 Edit: local dealer replaced torque tube assembly under warranty at ~8330 miles. Noise is gone, car sounds good. If anything else crops up,will update again.
Hey all! New to the forum and naturally my first post is somewhat of a help thread. Long story short, I surprised my wife Dec 2016 with a 2017 Grand Sport A8 in 2LT trim. We purchased it in FL but now live in a fairly remote part of Texas. The car has been a real gem and certainly breaks necks in this Sterling Blue color. A few hundred miles ago I thought I started to hear an odd tick but couldn’t put my finger on it. Fast forward today, car has almost 8600 miles on it and it seems to be knocking intermittently but heavily. It’s generally at low RPM or low-load and almost always happens while downshifting while coming to a halt. The local dealer does not have any Corvettes on their lot so I’m a bit weary of bringing it in. On the other hand, the closest large dealership is a three hour trek. I don’t want to stiff arm this problem further but any help or direction from the resident experts would be sincerely appreciated.
Cheers!
Hey all! New to the forum and naturally my first post is somewhat of a help thread. Long story short, I surprised my wife Dec 2016 with a 2017 Grand Sport A8 in 2LT trim. We purchased it in FL but now live in a fairly remote part of Texas. The car has been a real gem and certainly breaks necks in this Sterling Blue color. A few hundred miles ago I thought I started to hear an odd tick but couldn’t put my finger on it. Fast forward today, car has almost 8600 miles on it and it seems to be knocking intermittently but heavily. It’s generally at low RPM or low-load and almost always happens while downshifting while coming to a halt. The local dealer does not have any Corvettes on their lot so I’m a bit weary of bringing it in. On the other hand, the closest large dealership is a three hour trek. I don’t want to stiff arm this problem further but any help or direction from the resident experts would be sincerely appreciated.
Cheers!
Last edited by SterlingBlue; 02-21-2018 at 10:29 PM.
02-04-2018, 10:13 AM
#2
Le Mans Master
Sounds like something is rubbing. Definitely not normal...
02-04-2018, 10:28 AM
#3
Le Mans Master
That video says it all. Definitely not normal. I hope you get it sorted out.
02-04-2018, 10:29 AM
#4
Le Mans Master
Yeah, that's not right. As a wild guess, flexplate? But a dealer really needs to get in there and take it apart and figure it out.
I wouldn't worry too much about the lack of Vettes on the lot. If the tech is good, he or she is still good. This doesn't sound a Corvette-specific kind of issue anyway, unless it somehow involves the torque tube.
I wouldn't worry too much about the lack of Vettes on the lot. If the tech is good, he or she is still good. This doesn't sound a Corvette-specific kind of issue anyway, unless it somehow involves the torque tube.
02-04-2018, 11:15 AM
#5
Not normal and going to suggest it may be one of the following that is causing the rubbing/scraping noise in engine compartment.
Idler pulley.
Belt tensioner.
Water pump bearing failing.
Separated harmonic balancer.
I would take it to the nearest GM dealer at least to see if they can diagnose and fix it. In my opinion, I would not drive the car 3 hours away. Closer the better.
Idler pulley.
Belt tensioner.
Water pump bearing failing.
Separated harmonic balancer.
I would take it to the nearest GM dealer at least to see if they can diagnose and fix it. In my opinion, I would not drive the car 3 hours away. Closer the better.
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Skid Row Joe (02-05-2018)
02-04-2018, 11:39 AM
#6
It doesn't sound directly engine related as it is nowhere near engine rpm. Almost sounds like some part is loose from its mounting and banging around - maybe in the exhaust system. If you can raise the car on stands and look underneath you may be able to spot it.
In any case I'm sure a competent mechanic would be able to find it quickly. I also recommend just going to the closest dealer.
In any case I'm sure a competent mechanic would be able to find it quickly. I also recommend just going to the closest dealer.
02-04-2018, 12:08 PM
#8
Le Mans Master
I would bring it straight to a GM dealer. Hopefully it’s not too far from your house. It differently needs to be looked at, now.
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VettinFan (02-04-2018)
02-04-2018, 01:09 PM
#10
Race Director
If it were mine it'd be flat bedded to nearest dealer, asap.
Small stores have access to same support as larger ones for dealing w/ difficult issues so don't let dealer size put you off.
This is GM's to make right, let them. G/L
Small stores have access to same support as larger ones for dealing w/ difficult issues so don't let dealer size put you off.
This is GM's to make right, let them. G/L
02-04-2018, 04:27 PM
#11
Safety Car
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It doesn't sound directly engine related as it is nowhere near engine rpm. Almost sounds like some part is loose from its mounting and banging around - maybe in the exhaust system. If you can raise the car on stands and look underneath you may be able to spot it.
In any case I'm sure a competent mechanic would be able to find it quickly. I also recommend just going to the closest dealer.
In any case I'm sure a competent mechanic would be able to find it quickly. I also recommend just going to the closest dealer.
02-04-2018, 05:08 PM
#12
Safety Car
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That does not sound good at all. It almost sounds like it might be internal which is not good. I would not drive it at all like that. Keep us posted and good luck!
02-04-2018, 07:15 PM
#13
Melting Slicks
Something is loose, that's for sure. Good news is that it doesn't appear to be internal to the engine as it's not RPM dependent, as someone else previously mentioned.
If you're somewhat mechanically inclined and observant, I'd suggest putting the car in gear (forward & reverse) and see if the noise changes. If it does this would indicate something in the drive line is loose and knocking.
If it doesn't change under load (in gear) see if the noise changes tempo if you increase RPM. If so, perhaps something associated with the accessory belt.
If you're somewhat mechanically inclined and observant, I'd suggest putting the car in gear (forward & reverse) and see if the noise changes. If it does this would indicate something in the drive line is loose and knocking.
If it doesn't change under load (in gear) see if the noise changes tempo if you increase RPM. If so, perhaps something associated with the accessory belt.
02-04-2018, 07:30 PM
#14
Le Mans Master
maybe flex plate as posted??
02-04-2018, 10:45 PM
#15
Race Director
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I had to have the notoriously wonky harmonic balancer/pulley assembly replaced in my C5 this summer. No way I'd let the local twits touch it (boogied up something unrelated EVERY time it went in for minor warranty work when a baby, so put it on my trailer and took it to a dealer who actually sells AND SERVICES them. I didn't regret the bother in doing so when it came back all as it should be and nothing else screwed-up.
Are there good people in small dealerships who seldom see, let alone touch Vettes... sure, but I suspect were the study to be done it would produce results much like those in the medical profession, i.e., where surgery results are consistently the best is where the procedures of interest are most frequently performed. I'd hardly expect mechanics--excuse, me--"techs" to do any better.
Are there good people in small dealerships who seldom see, let alone touch Vettes... sure, but I suspect were the study to be done it would produce results much like those in the medical profession, i.e., where surgery results are consistently the best is where the procedures of interest are most frequently performed. I'd hardly expect mechanics--excuse, me--"techs" to do any better.
02-05-2018, 08:44 AM
#16
Thanks for all of the inputs! Will be making an appt with the local dealer today and should update you all is we get it figured out. I suppose it’s under warranty so we really have nothing to worry about because if the tech performs poor work I’m sure GM will have our backs.
Cheers
Cheers
02-05-2018, 10:22 AM
#17
Race Director
Definitely a warranty issue. Good luck.
02-05-2018, 12:10 PM
#19
Burning Brakes
