how long till it ruins ur rings
10-28-2010, 10:17 AM
#21
Without beating on it, IMO, you'll be fine. The new injectors are about 28% bigger. Unless you were already running really rich and your LTFT's (fuel trims) were already deep in negatives, the computer can lean you out by about 25%. Just dont beat on it, since in power enrich mode, the computer wont take negative fuel trims into account, and youll continue to run rich.
10-28-2010, 01:23 PM
#22
thanks, out of curiousity how did you determine that the injector was still being activated by the PCM when you had a misfire?
Misfire's from a tiny exhaust leak? I have been a tech for over 10 years, first time I heard that one. And you also said it had misfire's and ran perfectly fine... ?
Turning off an injector does not cause a lean condition, it causes it to not burn at all since there is no fuel present to burn, therefore it cannot be rich nor lean. It prevents cylinder wash down and damage due to it in the event of ignition failure on that cylinder. Such as ring/cylinder wall damage, oil contamination, catalytic converter failure.
I wish I could recall the application in which the injector was disabled on a misfiring cylinder, for some reason I was thinking this was a technology integrated into the 4th gen F body. There are automakers that do it, but off the top of my head I cannot remember the make of the vehicle that I encountered it on.
Just put your stock injectors in and drive to your tuner. Bring the 36# with you and install when you get there. Easy. I don't understand people wanting to risk their motor over a 15 minute task.
The car pulls timing, it does not shut off injectors. Leaning out an already misfiring cylinder would probably be the worst thing you could do.
The car pulls timing, it does not shut off injectors. Leaning out an already misfiring cylinder would probably be the worst thing you could do.
I wish I could recall the application in which the injector was disabled on a misfiring cylinder, for some reason I was thinking this was a technology integrated into the 4th gen F body. There are automakers that do it, but off the top of my head I cannot remember the make of the vehicle that I encountered it on.
10-28-2010, 05:27 PM
#23
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[quote]
Well have you never checked for noid on a dead cylinder while the vehicle was running? You will have injector pulse on the misfiring cylinder.
An exhaust leak at the manifold or header can cause a misfire.
quote]
Actualy when you have an injector down as soon as the 02 sees that bank is lean it will command fuel to the rest of the cylinders on that bank. Therefore it will be rich as hell.
Misfire's from a tiny exhaust leak? I have been a tech for over 10 years, first time I heard that one. And you also said it had misfire's and ran perfectly fine... ?
Turning off an injector does not cause a lean condition, it causes it to not burn at all since there is no fuel present to burn, therefore it cannot be rich nor lean.[/
Actualy when you have an injector down as soon as the 02 sees that bank is lean it will command fuel to the rest of the cylinders on that bank. Therefore it will be rich as hell.
10-28-2010, 07:23 PM
#25
[QUOTE=BaddBird;14052009]
Well have you never checked for noid on a dead cylinder while the vehicle was running? You will have injector pulse on the misfiring cylinder.
An exhaust leak at the manifold or header can cause a misfire.
quote]
Actualy when you have an injector down as soon as the 02 sees that bank is lean it will command fuel to the rest of the cylinders on that bank. Therefore it will be rich as hell. true story....
Well have you never checked for noid on a dead cylinder while the vehicle was running? You will have injector pulse on the misfiring cylinder.
An exhaust leak at the manifold or header can cause a misfire.
quote]
Actualy when you have an injector down as soon as the 02 sees that bank is lean it will command fuel to the rest of the cylinders on that bank. Therefore it will be rich as hell.
10-28-2010, 10:37 PM
#26
[QUOTE=BaddBird;14052009]
Well have you never checked for noid on a dead cylinder while the vehicle was running? You will have injector pulse on the misfiring cylinder.
An exhaust leak at the manifold or header can cause a misfire.
quote]
Actualy when you have an injector down as soon as the 02 sees that bank is lean it will command fuel to the rest of the cylinders on that bank. Therefore it will be rich as hell. Yes I have checked for "noid" on a misfiring cylinder, its one of the most basic steps to diagnosing a cyl misfire. Im not starting a pissing contest I was simply asking what your method of diag was, but you did give me the answer on how you confirmed that the injector was still being activated. I have also used many other methods to confirming injector activation and actual function, since noid will NOT tell you if the injector is actually delivering fuel on a misfiring cyl or any cyl for that matter.
I hope, but I don't think based on the responses though, that it's understood the message I was trying to deliver is there are systems that will shut down an injector when a cylinder misfires so it could steer someone wrong during diagnoses into thinking they have a driver malfunction in the computer or wiring issue when really the computer shut down the injector and the actual cause was an initial ignition malfunction.
The point that everyone missed is I posted that there is a management system on an OEM vehicle that unfortunately I cannot recall at the time that does actually shut down the injector on a misfiring cylinder, in that case you would not have a noid.
I have a very firm understanding of diagnosing drivability issues, Long and Short term fuel compensation etc.. so I understand what you are saying.
Also you quoted me for the exhaust leak comment, the point in that comment was the other poster said his car had a misfire and in the same sentence said the car ran perfectly fine, how does that work? He also said it was a tiny exhaust leak, I have worked on far more vehicles than I can count that a tiny exhaust leak had no affect what so ever on it misfiring, I know that exhaust leaks can cause issues, but a "tiny" exhaust leak is not going to cause a misfire.
Hope that clears up my points.
Well have you never checked for noid on a dead cylinder while the vehicle was running? You will have injector pulse on the misfiring cylinder.
An exhaust leak at the manifold or header can cause a misfire.
quote]
Actualy when you have an injector down as soon as the 02 sees that bank is lean it will command fuel to the rest of the cylinders on that bank. Therefore it will be rich as hell.
I hope, but I don't think based on the responses though, that it's understood the message I was trying to deliver is there are systems that will shut down an injector when a cylinder misfires so it could steer someone wrong during diagnoses into thinking they have a driver malfunction in the computer or wiring issue when really the computer shut down the injector and the actual cause was an initial ignition malfunction.
The point that everyone missed is I posted that there is a management system on an OEM vehicle that unfortunately I cannot recall at the time that does actually shut down the injector on a misfiring cylinder, in that case you would not have a noid.
I have a very firm understanding of diagnosing drivability issues, Long and Short term fuel compensation etc.. so I understand what you are saying.
Also you quoted me for the exhaust leak comment, the point in that comment was the other poster said his car had a misfire and in the same sentence said the car ran perfectly fine, how does that work? He also said it was a tiny exhaust leak, I have worked on far more vehicles than I can count that a tiny exhaust leak had no affect what so ever on it misfiring, I know that exhaust leaks can cause issues, but a "tiny" exhaust leak is not going to cause a misfire.
Hope that clears up my points.
Last edited by 00pooterSS; 10-28-2010 at 11:04 PM.
10-29-2010, 12:20 AM
#28
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If you are running extremely rich your computer will cut fuel and the engine will just hang, mine hung at 3000 rpm. I had codes for both banks rich after my engine swap, no damage.
10-29-2010, 12:31 AM
#29
Take it from me.......one of my brand new LSx 427ci engines was running rich. I drove it home from the shop that installed and tuned the engine.........then the next day my buddy came over to see it and go for a drive. He was in the back and I revved it and raw fuel shot out onto the ground about 6 feet out of each tail pipe. I drove it for 1 day, but it was about 50 miles worth.
Did a leakdown and all 8 cylinders were shot............engine had to come out and get honed and re-ringed.
Do not drive a new engine if its rich....period.
.
Did a leakdown and all 8 cylinders were shot............engine had to come out and get honed and re-ringed.
Do not drive a new engine if its rich....period.
.
10-29-2010, 12:36 AM
#30
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Pooter, I don't know what you're smoking, but you are all over the place, chill out, I dont think you know what you're talking about.
And yes, an exhaust leak can cause an o2 sensor to read lean, causing misfires. It can still run perfectly fine but the computer will report misfires.
A lot of people with big cams have tons of misfires at idle. The cars still run just fine.
And yes, an exhaust leak can cause an o2 sensor to read lean, causing misfires. It can still run perfectly fine but the computer will report misfires.
A lot of people with big cams have tons of misfires at idle. The cars still run just fine.
10-29-2010, 07:17 AM
#31
Can somebody explain why new engines/rings are more easily distroyed by cylinder washdown? After driving for an hour with a plug wire off my engine has showed no signs of trouble. I'm sure most of the fuel being injected was spit out the exhaust but I would imagine aleast a small amount had to pool on top of the piston/walls.
10-29-2010, 08:57 AM
#32
Take it from me.......one of my brand new LSx 427ci engines was running rich. I drove it home from the shop that installed and tuned the engine.........then the next day my buddy came over to see it and go for a drive. He was in the back and I revved it and raw fuel shot out onto the ground about 6 feet out of each tail pipe. I drove it for 1 day, but it was about 50 miles worth.
Did a leakdown and all 8 cylinders were shot............engine had to come out and get honed and re-ringed.
Do not drive a new engine if its rich....period.
.
Did a leakdown and all 8 cylinders were shot............engine had to come out and get honed and re-ringed.
Do not drive a new engine if its rich....period.
.
Also, I should note that its very likely that what you saw shooting out of the tail pipes was condensed water vapor. Water vapor is the second greatest component in exhaust gas. Its second only to nitrogen, an inert gas that passes largely unchanged through the engine. Water vapor is an even greater component than CO2 in exhaust gas. And far greater than any of the other noxious chemicals like carbon monoxide or NOx. Certainly if its running rich it will smell like fuel. If it were really fuel in the exhaust, you would have had major backfire issues, especially with a cam with any considerable overlap. IMO, of course.
Last edited by GuitsBoy; 10-29-2010 at 09:05 AM.
10-29-2010, 07:23 PM
#33
Pooter, I don't know what you're smoking, but you are all over the place, chill out, I dont think you know what you're talking about.
And yes, an exhaust leak can cause an o2 sensor to read lean, causing misfires. It can still run perfectly fine but the computer will report misfires.
A lot of people with big cams have tons of misfires at idle. The cars still run just fine.
And yes, an exhaust leak can cause an o2 sensor to read lean, causing misfires. It can still run perfectly fine but the computer will report misfires.
A lot of people with big cams have tons of misfires at idle. The cars still run just fine.
As far as exhausts leaks causing a lean condition, I am aware of that, but thats not what was said nor quoted. And a tiny exhaust leak by most people's definition would not cause a lean condition nor a misfire, maybe our definitions of "tiny" are different, a good sized to large leak could though, I agree. What I quoted was that you stated and still continue to say that the car misfired and ran perfectly fine, thats and oxymoron, it cannot run "perfectly fine" and "misfire" thats all I was getting at, and I'm smoking something??, and thats part of why I said I don't think anyone is actually following.
I wasn't smoking anything, but I was drinking plenty
10-29-2010, 08:08 PM
#34
Can somebody explain why new engines/rings are more easily distroyed by cylinder washdown? After driving for an hour with a plug wire off my engine has showed no signs of trouble. I'm sure most of the fuel being injected was spit out the exhaust but I would imagine aleast a small amount had to pool on top of the piston/walls.
The rings needing to be broken in and seated is why GuitsBoy said its not a good idea to do a leak down at 50 miles, they take a while to fully seat, and another little interesting fact, a cylinder with no oil on the rings or cylinder wall will not have compression, put a little oil in there and it will seal, oil actually fills the very tiny gap between the ring and cylinder wall. Once oil is on something it actually keeps things from contacting one another, the light film of oil seperates them.
10-29-2010, 08:55 PM
#35
I don't have a compression gauge should I spend the money to go get one and test the cylinder or would you guys not worry about it? Would and an hour with a dead plug normaly be enough to cause washdown and damage the rings/walls on a broken in engine? It seems to run fine its still very smooth and has good power but I worry that is I had lost some compression it wouldn't be enough to tell without a compression test.
Ps thanks for the help.
Ps thanks for the help.
10-29-2010, 09:17 PM
#36
I don't have a compression gauge should I spend the money to go get one and test the cylinder or would you guys not worry about it? Would and an hour with a dead plug normaly be enough to cause washdown and damage the rings/walls on a broken in engine? It seems to run fine its still very smooth and has good power but I worry that is I had lost some compression it wouldn't be enough to tell without a compression test.
Ps thanks for the help.
Ps thanks for the help.
And FYI, if it had damaged it enough to drop the compression a considerable amount it you would notice effects at idle first, if its really bad it will cause a constant misfire.
10-29-2010, 09:33 PM
#37
My car has a cam so I doubt id tell a difference/slight miss at idle. It deff doesn't have a misfire at all while driving. It sucks thinking I could be losing some power/performance from such a stupid thing. Id say its fine though I'm sure people have drove on engines with misfires before longer then an hour before without issues.
10-29-2010, 09:58 PM
#38
With only 50 miles on the car, there no way your rings would have been properly seated. Id be surprised if any car would do very well on a leakdown test that soon. What did the rings look like when you had it re-ringed? If you really had washdown issues, the damage should have been apparent. Also, you probably would have needed a full bore, not just honing the cylinders. I would have gotten a second opinion. Sounds to me like a shop that just wanted the work.
If its RICH as hell, the break-in process cannot happen and you will be screwed in just a a matter of 50 miles, maybe less. Then they will NOT seat. Some people get lucky and can run heavy weight regular oil to get them to seat, that did not work for me.
And it was a Lingenfelter built engine, they never ran it because it was a short block crate engine. Go tell them they have no clue what they're talking about. They leakdown checked it when they got the engine back to their shop and called and said the rings did not seat and it will need a hone and new rings. They did it for free thank god...........so I don't think the Lingenfelter shop just wanted the extra work...lol
Also, I should note that its very likely that what you saw shooting out of the tail pipes was condensed water vapor.
Water doesn't go through an exhaust and make it to the ground unless you have a blown head gasket.........the exhaust should be clean, clear and dry.
((of course in the morning the entire exhaust can be full of water from condensation overnight...which can cause a little squirt out the pipes onto the ground, but thats one spit and its over..))
I learned my lesson in getting a bullshit mail order tune.....especially where the complete jerkoff ******* tuner LOCKS the son-of-a-bitch because he thinks his tunes are something special........
.
10-30-2010, 09:03 AM
#39
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Yes I have checked for "noid" on a misfiring cylinder, its one of the most basic steps to diagnosing a cyl misfire. Im not starting a pissing contest I was simply asking what your method of diag was, but you did give me the answer on how you confirmed that the injector was still being activated. I have also used many other methods to confirming injector activation and actual function, since noid will NOT tell you if the injector is actually delivering fuel on a misfiring cyl or any cyl for that matter.
I hope, but I don't think based on the responses though, that it's understood the message I was trying to deliver is there are systems that will shut down an injector when a cylinder misfires so it could steer someone wrong during diagnoses into thinking they have a driver malfunction in the computer or wiring issue when really the computer shut down the injector and the actual cause was an initial ignition malfunction.
The point that everyone missed is I posted that there is a management system on an OEM vehicle that unfortunately I cannot recall at the time that does actually shut down the injector on a misfiring cylinder, in that case you would not have a noid.
The point that everyone missed is I posted that there is a management system on an OEM vehicle that unfortunately I cannot recall at the time that does actually shut down the injector on a misfiring cylinder, in that case you would not have a noid.
I have a very firm understanding of diagnosing drivability issues, Long and Short term fuel compensation etc.. so I understand what you are saying.
Turning off an injector does not cause a lean condition, it causes it to not burn at all since there is no fuel present to burn, therefore it cannot be rich nor lean.
Also you quoted me for the exhaust leak comment, the point in that comment was the other poster said his car had a misfire and in the same sentence said the car ran perfectly fine, how does that work? He also said it was a tiny exhaust leak, I have worked on far more vehicles than I can count that a tiny exhaust leak had no affect what so ever on it misfiring, I know that exhaust leaks can cause issues, but a "tiny" exhaust leak is not going to cause a misfire.
Hope that clears up my points
Hope that clears up my points
Last edited by BaddBird; 10-30-2010 at 12:31 PM.
10-30-2010, 02:45 PM
#40
First you suck at quoting so let me try to fix this.
Second, getting defensive, being passive aggressive calling me "super tech" and saying you backed something up I called you out is getting rediculous. That wasn't a call out, it was a question... You guys are in here thinking I am giving you **** when I have asked questions.
Third, you and phenomic keep saying misfire and running "perfectly" fine in the same sentance, not possible, never will be, misfire cannot equal running perfectly fine... Is that really that hard to understand?
I would have never even touched on that subject and went into wording that far if you guys didn't turn it into something it wasn't, all this owned bullshit and being a dick in your responses was not necessary when I asked questions like "can anyone confirm" "what was your method of diag" then everyone jumps the gun and turns into ******** and smartasses. If you read my responses you will see I refrained from deragatory comments until that crap started.
I'll quote just a couple things that stand out, the other things like saying you are certified for XX time, and pretty current I am not going to argue, based on you're ending remark I think on that one we both agree we don't know everything, I agree you know what you are talking about but the wording in some of the responses are incorrect and that is what I have responded to for the most part. Not trying to come off like im a "super tech" or that im perfect, calm down guys.
So you are saying a cylinder that is burning no fuel what so ever will be burning lean? You cannot burn lean nor rich if there is no fuel present so please explain that to me....
Lean and rich are relative to A/F ratio, so if there is no F in the A/F ratio how can it be lean?
As for your last comment that you made about exhaust leaks, a small exhaust leak can only cause a lean condition that can cause a misfire, in pretty much all cases a small exhaust leak is small, therefore it will not affect the A/F ratio enough to be considerable or picked up by the PCM to where the mixture could not be compensated for and would lean out enough to misfire, but I have not worked on every car made, just a very large amount of them because I was in independent owned shops for all my career up until the last year, now I am at Lexus. So I have worked on most vehicles that have ever seen the road, and I have yet to have a small exhaust leak cause that, now a decent sized leak is different. But I am NOT saying it is not possible, I do not know everything and never will.
But at least I know a misfiring engine does not run perfect
Im done...
Second, getting defensive, being passive aggressive calling me "super tech" and saying you backed something up I called you out is getting rediculous. That wasn't a call out, it was a question... You guys are in here thinking I am giving you **** when I have asked questions.
Third, you and phenomic keep saying misfire and running "perfectly" fine in the same sentance, not possible, never will be, misfire cannot equal running perfectly fine... Is that really that hard to understand?
I would have never even touched on that subject and went into wording that far if you guys didn't turn it into something it wasn't, all this owned bullshit and being a dick in your responses was not necessary when I asked questions like "can anyone confirm" "what was your method of diag" then everyone jumps the gun and turns into ******** and smartasses. If you read my responses you will see I refrained from deragatory comments until that crap started.
I'll quote just a couple things that stand out, the other things like saying you are certified for XX time, and pretty current I am not going to argue, based on you're ending remark I think on that one we both agree we don't know everything, I agree you know what you are talking about but the wording in some of the responses are incorrect and that is what I have responded to for the most part. Not trying to come off like im a "super tech" or that im perfect, calm down guys.
Originally Posted by 00pooterSS
Turning off an injector does not cause a lean condition, it causes it to not burn at all since there is no fuel present to burn, therefore it cannot be rich nor lean.
Lean and rich are relative to A/F ratio, so if there is no F in the A/F ratio how can it be lean?
As for your last comment that you made about exhaust leaks, a small exhaust leak can only cause a lean condition that can cause a misfire, in pretty much all cases a small exhaust leak is small, therefore it will not affect the A/F ratio enough to be considerable or picked up by the PCM to where the mixture could not be compensated for and would lean out enough to misfire, but I have not worked on every car made, just a very large amount of them because I was in independent owned shops for all my career up until the last year, now I am at Lexus. So I have worked on most vehicles that have ever seen the road, and I have yet to have a small exhaust leak cause that, now a decent sized leak is different. But I am NOT saying it is not possible, I do not know everything and never will.
But at least I know a misfiring engine does not run perfect
Im done...