Engine knocking / pinging
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 811
Likes: 0
From: RPV CA
Engine knocking / pinging
All of a sudden, I started hearing engine knocking or pinging. I really can't tell the difference of the two, but it sounds like more like knocking from cylinder 7 area. Could be spark plug misfire? I will try the motor tomorrow, but I am a little worried.
Oh, I always use Chevron 91 & the sound gets louder when the engine becomes normal operating temp.
It is going to be a long night.
:sad:
Oh, I always use Chevron 91 & the sound gets louder when the engine becomes normal operating temp.
It is going to be a long night.
:sad:
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Re: Engine knocking / pinging (dkdonkim)
Is it a knock while your standing over the running engine?
Or does it ping while your accelerating?
If you can stand over the engine and hear a knock while the engine is idling, then you've got problems :eek:
Or does it ping while your accelerating?
If you can stand over the engine and hear a knock while the engine is idling, then you've got problems :eek:
Race Director
Joined: May 2000
Posts: 14,542
Likes: 5
Re: Engine knocking / pinging (runamuk)
...If you can stand over the engine and hear a knock while the engine is idling, then you've got problems :eek:
It's probably "normal." :yesnod:
See these links, for example:
http://forums.corvetteforum.com/zerothread?id=282587
http://forums.corvetteforum.com/zerothread?id=205075
http://forums.corvetteforum.com/zerothread?id=607386
Does this sound like it:
"...may exhibit an engine knock noise that begins in the first 19,000-24,000 km (12,000-15,000 mi) of use. The knock noise is most often noticed during initial start-up and typically disappears within the first 5-30 seconds (may last longer in extreme cold temperatures). The noise is usually more noticeable on the initial start-up when the temperature is below 10°C (50°F) and may be more pronounced on the first cold start following a long trip.
This noise may be caused by an interaction between carbon that has formed on the piston, the piston motion and the cylinder wall. GM Powertrain Engineering, and an analysis of engines with this condition, has confirmed that the noise is not detrimental to the performance, reliability or durability of the engine. THIS NOISE DOES NOT HAVE ANY EFFECT ON THE LONGEVITY OF ANY OF THE ENGINE COMPONENTS."
If it does, this is GM's recommendation:
"Important -- At this time, attempts to repair this condition by replacing the engine assembly or pistons is not recommended."
What may work is getting rid of the carbon deposits. There are a number of methods to do this, all of them fairly messy.
Hope this helps! :smash:
[Modified by EHS, 2:43 PM 3/7/2004]
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 811
Likes: 0
From: RPV CA
Re: Engine knocking / pinging (EHS)
Thanks for the info.
So, I have to replace #7 piston? I have 04 Vert w/ less than 4K miles. Does it come w/ newly designed pistons yet?
H.M. :steering:
So, I have to replace #7 piston? I have 04 Vert w/ less than 4K miles. Does it come w/ newly designed pistons yet?
H.M. :steering:
Race Director
Joined: May 2000
Posts: 14,542
Likes: 5
Re: Engine knocking / pinging (dkdonkim)
Thanks for the info.
So, I have to replace #7 piston? I have 04 Vert w/ less than 4K miles. Does it come w/ newly designed pistons yet?
H.M. :steering:
So, I have to replace #7 piston? I have 04 Vert w/ less than 4K miles. Does it come w/ newly designed pistons yet?
H.M. :steering:
:banghead: :banghead: :banghead: Where does any of that say that?
Here, let me post it again in case you missed it the first time: :crazy: :crazy: :rolleyes: :rolleyes:
...If you can stand over the engine and hear a knock while the engine is idling, then you've got problems :eek:
Not necessarily. :nonod:
It's probably "normal." :yesnod:
See these links, for example:
http://forums.corvetteforum.com/zerothread?id=282587
http://forums.corvetteforum.com/zerothread?id=205075
http://forums.corvetteforum.com/zerothread?id=607386
Does this sound like it:
"...may exhibit an engine knock noise that begins in the first 19,000-24,000 km (12,000-15,000 mi) of use. The knock noise is most often noticed during initial start-up and typically disappears within the first 5-30 seconds (may last longer in extreme cold temperatures). The noise is usually more noticeable on the initial start-up when the temperature is below 10°C (50°F) and may be more pronounced on the first cold start following a long trip.
This noise may be caused by an interaction between carbon that has formed on the piston, the piston motion and the cylinder wall. GM Powertrain Engineering, and an analysis of engines with this condition, has confirmed that the noise is not detrimental to the performance, reliability or durability of the engine. THIS NOISE DOES NOT HAVE ANY EFFECT ON THE LONGEVITY OF ANY OF THE ENGINE COMPONENTS."
If it does, this is GM's recommendation:
"Important -- At this time, attempts to repair this condition by replacing the engine assembly or pistons is not recommended."
What may work is getting rid of the carbon deposits. There are a number of methods to do this, all of them fairly messy.
Hope this helps! :smash:
Not necessarily. :nonod:
It's probably "normal." :yesnod:
See these links, for example:
http://forums.corvetteforum.com/zerothread?id=282587
http://forums.corvetteforum.com/zerothread?id=205075
http://forums.corvetteforum.com/zerothread?id=607386
Does this sound like it:
"...may exhibit an engine knock noise that begins in the first 19,000-24,000 km (12,000-15,000 mi) of use. The knock noise is most often noticed during initial start-up and typically disappears within the first 5-30 seconds (may last longer in extreme cold temperatures). The noise is usually more noticeable on the initial start-up when the temperature is below 10°C (50°F) and may be more pronounced on the first cold start following a long trip.
This noise may be caused by an interaction between carbon that has formed on the piston, the piston motion and the cylinder wall. GM Powertrain Engineering, and an analysis of engines with this condition, has confirmed that the noise is not detrimental to the performance, reliability or durability of the engine. THIS NOISE DOES NOT HAVE ANY EFFECT ON THE LONGEVITY OF ANY OF THE ENGINE COMPONENTS."
If it does, this is GM's recommendation:
"Important -- At this time, attempts to repair this condition by replacing the engine assembly or pistons is not recommended."
What may work is getting rid of the carbon deposits. There are a number of methods to do this, all of them fairly messy.
Hope this helps! :smash:
I guess the question is does it cause any problems/damage?
Though it can be annoying,the piston slap on the C5 is not a durability issue.The piston slap is simply caused by the "short skirt" piston design utilized in the LS1 and many other high performance applications.Before the piston expands and reaches operating temperature,it tends to rock in the bore due to the short skirt design...It is the nature of the beast.
Since you have a brand new '04 car, with less than 4,000 miles, it's still under warranty. Why not take it to the dealer you bought it from for a diagnosis, rather than spending "a long night" trying to figure it out yourself. Part of the money you spent on the car was so that you no longer have to do that.
Cheers! Over and out. :seeya
[Modified by EHS, 2:59 PM 3/7/2004]
Drifting
Joined: Jan 2002
Posts: 1,498
Likes: 3
From: Sacramento CA
Re: Engine knocking / pinging (dkdonkim)
Pinging and Knocking are two VERY different sounds. Pinging sounds kind of like a diesel engine running, and Knocking is A LOT louder. It doesnt sound like it is going away either, like the others have suggested. I had a "knocking" noise, and it was a spun rod bearing. Be VERY carful how you use the car untill you have it diagnosed or you could have MAJOR problems.
