One Crazybad issue....
Thread Starter
Intermediate
Joined: Jul 2018
Posts: 34
Likes: 1
One Crazybad issue....
Hey Guys,
One crazy bad problem... My Ls3 is knocking with a rough idle and sounds like there is a metal on metal ticking noise ( Valve - or lifters?) . It has a flashing warning light for the check engine light. However, its just throwing the misfiring code. There is no smoke, no bad smells, no leaks or coolant in the oil. Not quite sure what this is.... The coils are all good and the plugs are all fine. I was thinking injectors but it would not account for that knocking metal on metal extreme noise.
Let me know whats going on. All ideas are helpful.
One crazy bad problem... My Ls3 is knocking with a rough idle and sounds like there is a metal on metal ticking noise ( Valve - or lifters?) . It has a flashing warning light for the check engine light. However, its just throwing the misfiring code. There is no smoke, no bad smells, no leaks or coolant in the oil. Not quite sure what this is.... The coils are all good and the plugs are all fine. I was thinking injectors but it would not account for that knocking metal on metal extreme noise.
Let me know whats going on. All ideas are helpful.
Race Director
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
Do not start again!
Either remove heads & inspect lifters/cam [for] damage yourself, or have it flat bedded to your wrench.
Do not start it again, George.
This ain't a bad belt/tensioner, those don't triggers a flashing CEL.
While it's not common per se, it's also not unheard of a LS3 eats a lifter.
Unfortunately lifter failures often wipe-out cam, also. Not always and why it's important not to run it.
A steady CEL is one thing, can continue operation while running down issue.
But, never a flashing CEL
Thread Starter
Intermediate
Joined: Jul 2018
Posts: 34
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George, a flashing CEL means STOP VEHICLE IMMEDIATELY.
Do not start again!
Either remove heads & inspect lifters/cam [for] damage yourself, or have it flat bedded to your wrench.
Do not start it again, George.
This ain't a bad belt/tensioner, those don't triggers a flashing CEL.
While it's not common per se, it's also not unheard of a LS3 eats a lifter.
Unfortunately lifter failures often wipe-out cam, also. Not always and why it's important not to run it.
A steady CEL is one thing, can continue operation while running down issue.
But, never a flashing CEL
Do not start again!
Either remove heads & inspect lifters/cam [for] damage yourself, or have it flat bedded to your wrench.
Do not start it again, George.
This ain't a bad belt/tensioner, those don't triggers a flashing CEL.
While it's not common per se, it's also not unheard of a LS3 eats a lifter.
Unfortunately lifter failures often wipe-out cam, also. Not always and why it's important not to run it.
A steady CEL is one thing, can continue operation while running down issue.
But, never a flashing CEL
OH I did not even move it.... I turned it off Instantly. Then Checked the code. I am not sure what to do. I just moved and left my truck up north so this was ..... my daily for the new job for about a month...... Oh well.
Any ideas let me know.
Race Director
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
Good it's not been operated.
At least it minimizes internal damage as well as metal particles flooding oiling system.
Only ideas I can posit are:
1) Dealer. Expensive as all get out. 'Nuff said.
2) Indep Shop. Preferably one specializing in HP builds & C6 if possible.
Since my AM warranty expired I use one for my '08 Z06, do excellent work and I'm in the sticks so they're out there.
Post where you are, George.
Local members reading this might be able to refer shop(s) you can trust who won't bolt you to a wall.
G/L, this too shall pass.
At least it minimizes internal damage as well as metal particles flooding oiling system.
Only ideas I can posit are:
1) Dealer. Expensive as all get out. 'Nuff said.
2) Indep Shop. Preferably one specializing in HP builds & C6 if possible.
Since my AM warranty expired I use one for my '08 Z06, do excellent work and I'm in the sticks so they're out there.
Post where you are, George.
Local members reading this might be able to refer shop(s) you can trust who won't bolt you to a wall.
G/L, this too shall pass.
Thread Starter
Intermediate
Joined: Jul 2018
Posts: 34
Likes: 1
Good it's not been operated.
At least it minimizes internal damage as well as metal particles flooding oiling system.
Only ideas I can posit are:
1) Dealer. Expensive as all get out. 'Nuff said.
2) Indep Shop. Preferably one specializing in HP builds & C6 if possible.
Since my AM warranty expired I use one for my '08 Z06, do excellent work and I'm in the sticks so they're out there.
Post where you are, George.
Local members reading this might be able to refer shop(s) you can trust who won't bolt you to a wall.
G/L, this too shall pass.
At least it minimizes internal damage as well as metal particles flooding oiling system.
Only ideas I can posit are:
1) Dealer. Expensive as all get out. 'Nuff said.
2) Indep Shop. Preferably one specializing in HP builds & C6 if possible.
Since my AM warranty expired I use one for my '08 Z06, do excellent work and I'm in the sticks so they're out there.
Post where you are, George.
Local members reading this might be able to refer shop(s) you can trust who won't bolt you to a wall.
G/L, this too shall pass.
Im out in the DC / Baltimore Metro Area. ANY help would appreciated. I could rebuild it myself but the issue is I no longer have a garage or a place to do it. Wishing I never moved....
Thread Starter
Intermediate
Joined: Jul 2018
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As far as I know flashing check engine light only happens for 1 reason, when the misfire is bad enough that it could harm the engine ( really it melts the cat, maybe risks the exhaust valves)
misfire diagnostic looks at the rate of change of the engine speed and correlates that to detect the lack of a power stroke. So it is possible that you had complete misfire on a cylinder.
flashing check engine light does mean turn off engine immediately, but as far as I know it’s to protect the cats.
you said the bad engine noise sounds like valve train noise. If I were you I’d pull the valve covers off and see if I can find a broken spring ? Dropped valve? Damaged rocker? This is the least intrusive , no special tools needed, very quick check to look around. Next You could pull the spark plugs and put a usb boroscope in the chambers and see if any valves hit the pistons. Next up I guess would be checking lifters, but that’s more work cause you have to pull the heads.
edit: post a list of mods, mileage, how do you use the car, age, previous work, etc.
misfire diagnostic looks at the rate of change of the engine speed and correlates that to detect the lack of a power stroke. So it is possible that you had complete misfire on a cylinder.
flashing check engine light does mean turn off engine immediately, but as far as I know it’s to protect the cats.
you said the bad engine noise sounds like valve train noise. If I were you I’d pull the valve covers off and see if I can find a broken spring ? Dropped valve? Damaged rocker? This is the least intrusive , no special tools needed, very quick check to look around. Next You could pull the spark plugs and put a usb boroscope in the chambers and see if any valves hit the pistons. Next up I guess would be checking lifters, but that’s more work cause you have to pull the heads.
edit: post a list of mods, mileage, how do you use the car, age, previous work, etc.
Last edited by luka2sb; May 29, 2019 at 08:25 PM.
Thread Starter
Intermediate
Joined: Jul 2018
Posts: 34
Likes: 1
As far as I know flashing check engine light only happens for 1 reason, when the misfire is bad enough that it could harm the engine ( really it melts the cat, maybe risks the exhaust valves)
misfire diagnostic looks at the rate of change of the engine speed and correlates that to detect the lack of a power stroke. So it is possible that you had complete misfire on a cylinder.
flashing check engine light does mean turn off engine immediately, but as far as I know it’s to protect the cats.
you said the bad engine noise sounds like valve train noise. If I were you I’d pull the valve covers off and see if I can find a broken spring ? Dropped valve? Damaged rocker? This is the least intrusive , no special tools needed, very quick check to look around. Next You could pull the spark plugs and put a usb boroscope in the chambers and see if any valves hit the pistons. Next up I guess would be checking lifters, but that’s more work cause you have to pull the heads.
edit: post a list of mods, mileage, how do you use the car, age, previous work, etc.
misfire diagnostic looks at the rate of change of the engine speed and correlates that to detect the lack of a power stroke. So it is possible that you had complete misfire on a cylinder.
flashing check engine light does mean turn off engine immediately, but as far as I know it’s to protect the cats.
you said the bad engine noise sounds like valve train noise. If I were you I’d pull the valve covers off and see if I can find a broken spring ? Dropped valve? Damaged rocker? This is the least intrusive , no special tools needed, very quick check to look around. Next You could pull the spark plugs and put a usb boroscope in the chambers and see if any valves hit the pistons. Next up I guess would be checking lifters, but that’s more work cause you have to pull the heads.
edit: post a list of mods, mileage, how do you use the car, age, previous work, etc.
I just drive it 40 miles a day lately at most. for a month. its an 08. I have had it since 09. Stock --- 0 nothing done to it. Just simple maintenance like plugs wires, belts, fluid changes. 100kmiles .. RAN perfect until i filled up at this gas station I always do... starting running rough when I got it home. I do not drive it hard. I have never even needed to change the clutch... yet.....
I am going to post it forsale or salvage. I can not afford to fix it nor do I have the time nor the place to keep it. SO if you want it let me know. Most likely itll be scrapped.
Last edited by George Karpin; May 29, 2019 at 09:00 PM.
Pro
Joined: Sep 2016
Posts: 640
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From: Texas
I just drive it 40 miles a day lately at most. for a month. its an 08. I have had it since 09. Stock --- 0 nothing done to it. Just simple maintenance like plugs wires, belts, fluid changes. 100kmiles .. RAN perfect until i filled up at this gas station I always do... starting running rough when I got it home. I do not drive it hard. I have never even needed to change the clutch... yet.....
I am going to post it forsale or salvage. I can not afford to fix it nor do I have the time nor the place to keep it. SO if you want it let me know. Most likely itll be scrapped.
I am going to post it forsale or salvage. I can not afford to fix it nor do I have the time nor the place to keep it. SO if you want it let me know. Most likely itll be scrapped.
Burning Brakes
Joined: May 2000
Posts: 1,097
Likes: 191
From: Vienna VA
You should at least get it checked out to see what the problem is. It could be something simple or it could be catastrophic. Either way, you'll want to know before you sell it and any buyer would want to know.
Race Director
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
In the meantime let it sit where ever it's parked until a place to store it can be located until time/resources permit issue be addressed, properly.
Concurrently procure a beater capable of getting 40 mi p/day to/from job, can't be difficult, maybe someone you're working with? A friend's friend? Pickle lot? Craig's List?
Being horribly squeezed due to personal circumstances is awful and usually breeds rash judgement/decisions.
Circumstances change George and usually for the better, move towards that change.
Find a way to put this entire matter on hold for now, concentrate on family/job & settling-in post move. Priorities.
Selling as 'scrap' is not the solution, not now.
In golf players getting themselves into trouble must 'scramble'.
We all must do a little scrambling in life, now's your time for a little scrambling.
Race Director
Joined: Dec 2002
Posts: 10,468
Likes: 1,149
From: Wayne Township WI
Him, me or both. 
Can only take a poster at their word, until they prove otherwise.
Guy sounds desperate, been there done that w/ a '69 roadster I had when 18.
To a dumb kid being forced to lose $2.5K seemed disastrous.
Old enough to recall what $2.5K meant in '71?
OP needs workable solutions right now and even then, he has to make final decision.
Still he said it's an LS3, minimally '08.
Claims it's led a quiet life, low mile, a lightly used C6 has value well beyond scrap.
WTH w/could a new cam w/ lifters possibly cost? $2K? $3K? Peanuts for many, bank breaker for others. Attainable to all.
Selling it @ scrap value means some jamoke replaces lifters/cam & resells between wholesale/retail.
Huge profit jamoke makes is OP's money & OP's wrong headed, IMO.
If he can't afford to have problem diagnosed much less fixed, how can he afford another car to drive?
Guy sounds desperate, been there done that w/ a '69 roadster I had when 18.
To a dumb kid being forced to lose $2.5K seemed disastrous.
Old enough to recall what $2.5K meant in '71?
OP needs workable solutions right now and even then, he has to make final decision.
Still he said it's an LS3, minimally '08.
Claims it's led a quiet life, low mile, a lightly used C6 has value well beyond scrap.
WTH w/could a new cam w/ lifters possibly cost? $2K? $3K? Peanuts for many, bank breaker for others. Attainable to all.
Selling it @ scrap value means some jamoke replaces lifters/cam & resells between wholesale/retail.
Huge profit jamoke makes is OP's money & OP's wrong headed, IMO.
Racer
Joined: Nov 2009
Posts: 312
Likes: 60
From: VA
OP, I had a similiar problem a lil over a year ago. I ended up having a broken valve spring, which wasn't too hard to fix. I was lucky that the valve didn't drop inside.... Anyways, below is the link to my thread about the troubleshooting I went through and the help I received from the fine peoples on these boards like Landru....
Misfire and Knocking on LS3
Good luck man!
Misfire and Knocking on LS3
Good luck man!
Last edited by whiteboy444; May 30, 2019 at 11:42 AM.
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Joined: Aug 2006
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Him, me or both.
Can only take a poster at their word, until they prove otherwise.
Guy sounds desperate, been there done that w/ a '69 roadster I had when 18.
To a dumb kid being forced to lose $2.5K seemed disastrous.
Old enough to recall what $2.5K meant in '71?
OP needs workable solutions right now and even then, he has to make final decision.
Still he said it's an LS3, minimally '08.
Claims it's led a quiet life, low mile, a lightly used C6 has value well beyond scrap.
WTH w/could a new cam w/ lifters possibly cost? $2K? $3K? Peanuts for many, bank breaker for others. Attainable to all.
Selling it @ scrap value means some jamoke replaces lifters/cam & resells between wholesale/retail.
Huge profit jamoke makes is OP's money & OP's wrong headed, IMO.
Can only take a poster at their word, until they prove otherwise.
Guy sounds desperate, been there done that w/ a '69 roadster I had when 18.
To a dumb kid being forced to lose $2.5K seemed disastrous.
Old enough to recall what $2.5K meant in '71?
OP needs workable solutions right now and even then, he has to make final decision.
Still he said it's an LS3, minimally '08.
Claims it's led a quiet life, low mile, a lightly used C6 has value well beyond scrap.
WTH w/could a new cam w/ lifters possibly cost? $2K? $3K? Peanuts for many, bank breaker for others. Attainable to all.
Selling it @ scrap value means some jamoke replaces lifters/cam & resells between wholesale/retail.
Huge profit jamoke makes is OP's money & OP's wrong headed, IMO.
And no your not a
.
Thread Starter
Intermediate
Joined: Jul 2018
Posts: 34
Likes: 1
You seem to know everything.... You don't know how that ended. Or that we were able to repair it with help from people on this forum.
You seem to know everyone on here personally. If i was a troll wouldn't I go around trolling your crap posts and use my fake awesome user name. You're real on top of it.
Thanks for being a real big Richard.
Thread Starter
Intermediate
Joined: Jul 2018
Posts: 34
Likes: 1
For Heaven's sake George take a breath, back away from this a couple days, it'll provide a perspective.
In the meantime let it sit where ever it's parked until a place to store it can be located until time/resources permit issue be addressed, properly.
Concurrently procure a beater capable of getting 40 mi p/day to/from job, can't be difficult, maybe someone you're working with? A friend's friend? Pickle lot? Craig's List?
Being horribly squeezed due to personal circumstances is awful and usually breeds rash judgement/decisions.
Circumstances change George and usually for the better, move towards that change.
Find a way to put this entire matter on hold for now, concentrate on family/job & settling-in post move. Priorities.
Selling as 'scrap' is not the solution, not now.
In golf players getting themselves into trouble must 'scramble'.
We all must do a little scrambling in life, now's your time for a little scrambling.
In the meantime let it sit where ever it's parked until a place to store it can be located until time/resources permit issue be addressed, properly.
Concurrently procure a beater capable of getting 40 mi p/day to/from job, can't be difficult, maybe someone you're working with? A friend's friend? Pickle lot? Craig's List?
Being horribly squeezed due to personal circumstances is awful and usually breeds rash judgement/decisions.
Circumstances change George and usually for the better, move towards that change.
Find a way to put this entire matter on hold for now, concentrate on family/job & settling-in post move. Priorities.
Selling as 'scrap' is not the solution, not now.
In golf players getting themselves into trouble must 'scramble'.
We all must do a little scrambling in life, now's your time for a little scrambling.
Thanks for the vote of confidence. I had to sell just about everything to move away from a bad situation to just about worse one at this point. Tried to keep the car but that's about all i had left. I'm lucky its parked in a lot where the owner told me itll be safe for a week or so. To be honest I really need to money and wish i sold it now before i moved but always hard to get rid of things you love