How much noise
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Drifting
Joined: Feb 2004
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From: Katy TX
St. Jude Donor '08-'09
How much noise
can an injector make? When i start the car up, there is a loud erratic clacking coming from the engine. It isnt a knock. I have gotten a stethoscope and checked the rocker covers and everything sounds normal.
The clacking goes away after about a couple of miles. Is it possible that i am loosing fuel pressure at one or two injectors and that is the sound i am hearing?
The clacking goes away after about a couple of miles. Is it possible that i am loosing fuel pressure at one or two injectors and that is the sound i am hearing?
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From: Dyer, IN
can an injector make? When i start the car up, there is a loud erratic clacking coming from the engine. It isnt a knock. I have gotten a stethoscope and checked the rocker covers and everything sounds normal.
The clacking goes away after about a couple of miles. Is it possible that i am loosing fuel pressure at one or two injectors and that is the sound i am hearing?
The clacking goes away after about a couple of miles. Is it possible that i am loosing fuel pressure at one or two injectors and that is the sound i am hearing?
You've got the stethoscope....did you isolate the noise to an injector?
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Standard fare LS piston slap.
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It's your lifters draining down. Mine does the same thing.
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
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Drifting
Joined: Feb 2004
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From: Katy TX
St. Jude Donor '08-'09
It's your lifters draining down. Mine does the same thing.
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
And it is NOT piston slap. But just how loud can the injectors be, and would they be loud then finally have the noise go away? I was going to check these tonight after work and thought i would ask.
My oil pressure runs 55 at idle and 80 at 2500 and up, no, nogo there.
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it has been doing this for about the last 3 months. And it doesnt do it all of the time. I have listened to the lifters through the cover and i have always been able to tell in the past, but they dont sound any different. And the other poster is right, it feeds from a common manifold
But just how loud can the injectors be, and would they be loud then finally have the noise go away?
Last edited by wcsinx; Oct 12, 2009 at 12:59 PM.
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From: Howell Michigan
St. Jude Donor '09-'10-'11
Check all the spark plug wires are on the coil and plugs tightly too. You can pull the electrical plug off one injector at a time to help identify if one is louder then the rest.
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It's your lifters draining down. Mine does the same thing.
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
I also won't tell you that a change in filters and oil will not make this go away.
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*shrug* It actually has worked for some. There was another thread which I'm having no luck finding where someone specifically mentioned that combination eliminated his startup clacking. So I have my fingers crossed.
Thread Starter
Drifting
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From: Katy TX
St. Jude Donor '08-'09
Found it. #7 exhaust lifter is making the noise. Couldnt hear it until we put the scope on the header.
Before tearing everything down, im going to seafoam the engine and see
if it frees it up. if not, then ill start the replacement.
Thanks all.
Before tearing everything down, im going to seafoam the engine and see
if it frees it up. if not, then ill start the replacement.
Thanks all.
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Keep us posted on your results. I assure you, you're not the only one with this issue!
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Drifting
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From: Katy TX
St. Jude Donor '08-'09
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From: Howell Michigan
St. Jude Donor '09-'10-'11
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Before tearing things down, you might want to swap the rocker and pushrod with a different cylinder. If the noise stays at the same location then lifter is likely. If it switches to the other cylinder then bent pushrod, or rocker with missing roller needles may be at falt.
Thread Starter
Drifting
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From: Katy TX
St. Jude Donor '08-'09
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From: Howell Michigan
St. Jude Donor '09-'10-'11
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From: Howell Michigan
St. Jude Donor '09-'10-'11
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From: Duncan South Carolina
St. Jude Donor '10
It's your lifters draining down. Mine does the same thing.
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!
(Yes, I know what piston slap sounds like, this is not piston slap, it sounds nothing like piston slap, don't tell me it's piston slap)
I've heard a number of people here describe the same thing with their engines. I've also personally heard a friend's Z06 make the same noise after he swore up and down it didn't. It's a very common topic on LSX boards as well. Soooo take it for it is. Which is to say a minor annoyance. If it keeps tapping after a mile or two then I'd start to worry.
I know at least one guy on this forum claims his startup tapping went away when he switched to Wix oil filters because supposedly they're better at suspending oil in the engine. So I got a couple of those on hand for the next oil change. I'm also going to switch to Castrol Edge oil. We'll see!