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Need help diagnosing engine "knock"

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Old Jul 18, 2014 | 08:05 PM
  #1  
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Default Need help diagnosing engine "knock"

I've got a "knock" coming from my engine. It seems to be located on the left side (drivers side) of the motor. Not sure what it could be, but I've attached a link to a youtube clip of it.

Anyone have any idea what I should start looking at to diagnose the issue?

I don't drive the car much (less than 100 miles per summer), and I believe it's been doing it since I purchased the car (4 years ago). I've just now been able to get to trying to figure out what the issue is (if any, maybe I'm just hearing a normal engine).

Any help is much appreciated!!

https://www.youtube.com/watch?v=fGY-...ature=youtu.be
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Old Jul 18, 2014 | 08:30 PM
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Originally Posted by Petes75Vette
I've got a "knock" coming from my engine. It seems to be located on the left side (drivers side) of the motor. Not sure what it could be, but I've attached a link to a youtube clip of it.

Anyone have any idea what I should start looking at to diagnose the issue?

I don't drive the car much (less than 100 miles per summer), and I believe it's been doing it since I purchased the car (4 years ago). I've just now been able to get to trying to figure out what the issue is (if any, maybe I'm just hearing a normal engine).

Any help is much appreciated!!

https://www.youtube.com/watch?v=fGY-...ature=youtu.be

On my crappy laptop speakers that just sounds like a blown header gasket.
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Old Jul 18, 2014 | 08:35 PM
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sounds more like a tick, maybe exhaust leak
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Old Jul 18, 2014 | 08:43 PM
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Originally Posted by ConnecticutJunkman
On my crappy laptop speakers that just sounds like a blown header gasket.
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Old Jul 18, 2014 | 10:55 PM
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From: Oxford MA-----You just lost the game!!!!
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Yeah, man, that sounds like an exhaust leak. Take a piece of hose, put one end up to your ear, and hunt around with the other end, you should be able to easily find exactly where it's coming from. Perhaps new header gaskets are in order.

Scott
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Old Jul 18, 2014 | 11:54 PM
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Originally Posted by ConnecticutJunkman
On my crappy laptop speakers that just sounds like a blown header gasket.
Ditto my iPad mini speakers.

Pete
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Old Jul 30, 2014 | 09:31 PM
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Thanks guy.

After researching more, I think its a blown head gasket. I seem to have oil in my coolant overflow tank, and underneath the car it looks like my engine is "sweating" oil. That is, it seems as if oil is just kind of all over everything down there, in a very thin film (this being after the car sat all winter and I had a look under).

My trans pan gasket let go over the winter, and I just replaced that + filter. Added new fluid, drove around the block, and noticed when I pulled in that my coolant overflow tank was bubbling. I didn't drive it far enough to heat up, and the fan hadn't even kicked in yet (the temp was low). I figured it was boiling, but it was more than likely air bubbling out now that I'm reading about the head gasket. This is what led me to decide to start diagnosing the noise to see if that played a role in anything...and sure enough, it seems that I've got all the symptoms of that noise being the culprit of a head gasket blown and these other issues (dirty coolant + bubbling).

Guess it's time to learn how to take apart a motor. Although I'd consider myself an advanced DIY'er around the house...this Vette was my introduction to working on cars deeper than just oil and wiper blade changes. To this point I've learned a lot, and time to go slow and learn a whole heck of a lot more I guess.
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Old Jul 30, 2014 | 09:58 PM
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From: Oxford MA-----You just lost the game!!!!
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Originally Posted by Petes75Vette
Thanks guy.

After researching more, I think its a blown head gasket. I seem to have oil in my coolant overflow tank, and underneath the car it looks like my engine is "sweating" oil. That is, it seems as if oil is just kind of all over everything down there, in a very thin film (this being after the car sat all winter and I had a look under).

My trans pan gasket let go over the winter, and I just replaced that + filter. Added new fluid, drove around the block, and noticed when I pulled in that my coolant overflow tank was bubbling. I didn't drive it far enough to heat up, and the fan hadn't even kicked in yet (the temp was low). I figured it was boiling, but it was more than likely air bubbling out now that I'm reading about the head gasket. This is what led me to decide to start diagnosing the noise to see if that played a role in anything...and sure enough, it seems that I've got all the symptoms of that noise being the culprit of a head gasket blown and these other issues (dirty coolant + bubbling).

Guess it's time to learn how to take apart a motor. Although I'd consider myself an advanced DIY'er around the house...this Vette was my introduction to working on cars deeper than just oil and wiper blade changes. To this point I've learned a lot, and time to go slow and learn a whole heck of a lot more I guess.
If you are an "advanced DIY'er" around the house, then you know that most things aren't as hard to do as it looks, once you do a little research, and get a little experience. Same with automotive type stuff, you may need a few new tools is all. I think you'll be in good shape. If you can fix a leaky faucet, you can work on a car.

(And if you can dodge a wrench, you can dodge a ball!)

Scott
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