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07/14/2009 06:38:01 PM · #26 |
Originally posted by DrAchoo:
At least they have good reviews on Car Talk which is where I found them in the first place. |
Those are some great testimonies! I might have to make the three hour trip to Eugene to have my cat converter replaced. |
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07/14/2009 06:42:32 PM · #27 |
| Even more reviews. I'm hoping it bears out for me. One hates to just dump $1500. That's 3/5ths of a 5DmkII or 3/5ths of a new gas fireplace or most of an outside gas firepit or a.... :( |
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07/14/2009 06:47:26 PM · #28 |
I would offer help, but since I'm a dealer mechanic(although not on imports) and you avoid them like the plague, so I'll just sit back and watch what happens.
Matt |
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07/14/2009 07:00:25 PM · #29 |
Originally posted by MattO:
I would offer help, but since I'm a dealer mechanic(although not on imports) and you avoid them like the plague, so I'll just sit back and watch what happens. |
If you can plead with Matt here a little, you'll learn something......8>)
Couple 'o things.....
In these days of computer engine management, burnt valves are extremely rare.
I'm not sure how effective a cylinder leakdown test would be as I stated earlier on a couple of counts, not the least of which trying to get accurate information on how to ensure the camshaft(s) position to have an accurate reading.....it usually requires that the engine be at an exact spot so that the compressed air doesn't force the piston to move to a point where the valves open.
There is some history with Subaru engines dislodging valve seats, but usually not at this very low mileage and not generally without provocation......i.e., overheating the engine, or an injector sticking and causing a lean/overheat condition in the combustion chamber.
Really, I would lean toward taking it to Subaru and not losing too much sleep over it or getting too worked up 'til you have some competent testing done.
As far as an earlier comment on leakdown tests in basis not being helpful, back in the day, they were simple & straightforward.......pump air into the cylinder through the plughole, prop open the throttle plate, have the rocker arms off, or loose, and if it pumps air out the carb, bad intake valve; air out the exhaust pipe, bad exhaust valve; air out the oil fill tube, or just blowing at you through the open valve cover, rings....
But that was back when engines were simple & crude.
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07/14/2009 07:14:20 PM · #30 |
Originally posted by MattO:
I would offer help, but since I'm a dealer mechanic(although not on imports) and you avoid them like the plague, so I'll just sit back and watch what happens.
Matt |
Haha. Well, I can never please you. I know you aren't the problem..only stuck in a system that is part of the problem. ;) I can't remember, aren't you a Beemer guy anyway? |
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07/14/2009 07:19:32 PM · #31 |
Originally posted by NikonJeb:
Originally posted by MattO:
I would offer help, but since I'm a dealer mechanic(although not on imports) and you avoid them like the plague, so I'll just sit back and watch what happens. |
If you can plead with Matt here a little, you'll learn something......8>)
Couple 'o things.....
In these days of computer engine management, burnt valves are extremely rare.
I'm not sure how effective a cylinder leakdown test would be as I stated earlier on a couple of counts, not the least of which trying to get accurate information on how to ensure the camshaft(s) position to have an accurate reading.....it usually requires that the engine be at an exact spot so that the compressed air doesn't force the piston to move to a point where the valves open.
There is some history with Subaru engines dislodging valve seats, but usually not at this very low mileage and not generally without provocation......i.e., overheating the engine, or an injector sticking and causing a lean/overheat condition in the combustion chamber.
Really, I would lean toward taking it to Subaru and not losing too much sleep over it or getting too worked up 'til you have some competent testing done.
As far as an earlier comment on leakdown tests in basis not being helpful, back in the day, they were simple & straightforward.......pump air into the cylinder through the plughole, prop open the throttle plate, have the rocker arms off, or loose, and if it pumps air out the carb, bad intake valve; air out the exhaust pipe, bad exhaust valve; air out the oil fill tube, or just blowing at you through the open valve cover, rings....
But that was back when engines were simple & crude. |
The compression test, however, should be straightforward right? So I assume we have the problem narrowed down to the proper cylinder. Coincidentally (which may not be), there was a small gash on the spark plug wire to that cylinder. We also have a misfire cylinder error on cylinder #2. Am I thinking correctly that there really is no further diagnostic test available to anybody else without taking the head off? And when the head is off you are already talking $800 and it's unlikely you would find a problem that didn't need the head to come off anyway?
Look at it this way. Can you think of a problem that would give you a misfire error, a bad compression test, possibly a bad leak down test (depending on whether you trust it or not) that doesn't need the head to come off? |
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07/14/2009 07:23:04 PM · #32 |
Originally posted by DrAchoo:
I bet people feel like this when they go to the doctor... |
I am a do it your self doctor kind of guy, maybe I'll try surgery on myself some day....:P |
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07/14/2009 07:23:32 PM · #33 |
Originally posted by PapaBob:
Originally posted by DrAchoo:
I bet people feel like this when they go to the doctor... |
I am a do it your self doctor kind of guy, maybe I'll try surgery on myself some day....:P |
Make sure you stay at a Holiday Inn Express... |
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07/14/2009 07:30:34 PM · #34 |
Originally posted by DrAchoo:
Look at it this way. Can you think of a problem that would give you a misfire error, a bad compression test, possibly a bad leak down test (depending on whether you trust it or not) that doesn't need the head to come off? |
Yep sure can depending on the type of cam follower lash assembly that the engine uses.
Further testing should include a relative compression test, running compression test, I'd also suggest a good look at the fuel trims and adaptive fuel curves for that bank of cylinders at idle and 2500 RPM's. I'd also suggest to see if there has been a reflash done on the computer and if the injectors have been looked at for flow, what are the O2 sensors doing at doing at idle and 2500 RPM and how well they respond to additional fuel from an outside source.
Matt |
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07/14/2009 07:41:36 PM · #35 |
Originally posted by MattO:
Originally posted by DrAchoo:
Look at it this way. Can you think of a problem that would give you a misfire error, a bad compression test, possibly a bad leak down test (depending on whether you trust it or not) that doesn't need the head to come off? |
Yep sure can depending on the type of cam follower lash assembly that the engine uses.
Further testing should include a relative compression test, running compression test, I'd also suggest a good look at the fuel trims and adaptive fuel curves for that bank of cylinders at idle and 2500 RPM's. I'd also suggest to see if there has been a reflash done on the computer and if the injectors have been looked at for flow, what are the O2 sensors doing at doing at idle and 2500 RPM and how well they respond to additional fuel from an outside source.
Matt |
So as far as the fuel issues, wouldn't they affect either all cylinders or at least the one side? (it's only a 4-cylinder). I catch ya thinking maybe it's the injector for that cylinder. That makes sense to me, although I suppose the mechanic guy goes back to the fact there are no other errors on the computer. I think he's putting some diagnostic weight in that matter, although I could just be reading something in our conversation that isn't there. |
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07/14/2009 08:57:25 PM · #36 |
| why not just go to the proper motor mechanic in the first place.It may cost you a bit more, but it better than you attempting to dissect everything so you can do it yourself, or have a mechanic that does not have first hand experience in this motor, |
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07/14/2009 09:38:05 PM · #37 |
Originally posted by JulietNN:
why not just go to the proper motor mechanic in the first place.It may cost you a bit more, but it better than you attempting to dissect everything so you can do it yourself, or have a mechanic that does not have first hand experience in this motor, |
Umm, I am not doing it myself and the mechanic DOES have a first hand experience with the motor. What gave you this impression? |
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07/14/2009 09:43:59 PM · #38 |
| Just the whole thread, it seems like you do not trust him. |
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07/14/2009 10:04:07 PM · #39 |
Originally posted by JulietNN:
Just the whole thread, it seems like you do not trust him. |
You know, it's probably more a matter of being a control freak. Being helpless from ignorance is not a fun place to be in. After reading the reviews about him and after talking to him for 20 minutes I do feel like I trust him, but I just wonder about the correct diagnosis because we are talking about something which is apparently very uncommon. But the Subaru guy, at least on the phone, wasn't much more help. He said he had never seen a burnt valve before on an Outback. The problem comes in that you are committing money (and possibly significant money) just to figure out the problem. In the end I decided I was just as well off with this guy because it saves me some time (being on a deadline) and I felt like he was trustworthy.
I'll update everybody on the final diagnosis, the final price and whether it fixed everything as the info comes in. |
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07/14/2009 10:29:21 PM · #40 |
Originally posted by PapaBob:
Originally posted by DrAchoo:
I bet people feel like this when they go to the doctor... |
I am a do it your self doctor kind of guy, maybe I'll try surgery on myself some day....:P |
Holy crap, I read this, then was browsing fark.com and found this link:
Woman performs plastic surgery on herself
WHY?! |
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07/14/2009 10:31:37 PM · #41 |
You got a more in-depth look at possible avenues of repair from Matt.
Listen.
You can get an accurate diagnosis without having to pull the head.
But......you have to find the right person to do so.
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07/14/2009 10:33:06 PM · #42 |
| Just so you know - a loose gas cap can cause the Check Engine light to come on. However, I seriously doubt in that case the fault code would indicate cylinder #2. Good luck. |
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07/14/2009 10:48:13 PM · #43 |
I was a line mechanic at a Ford garage in 1970, and a 1/4 mile racing mechanic before that. I have plenty of experience with engines. If you want to find out if the compression is low on one or more cylinders here is the easy and quick way to do it.
1: Disable the spark. You can do this by pulling off the plug wires, or by removing power to the coil or coils.
2: Hold the throttle open.
3: Turn the engine over with the starter for 10 or 15 seconds and listen carefully to the rhythm of the sound.
4: If it is an even sounding purr (aside from the noise of the starter and ring gear) then everything is probably ok.
5: If it sounds uneven i/e you can hear 3 cylinders in rhythm, then the 4th one comes by much quicker, then there is one cylinder with low compression.
It's that simple.
If you don't know how the rhythm should sound, then pull out one spark plug and do it again. Listen to the rhythm. The sound of the air blowing out of the open plug will indicate the time period that the engine should be turning through 4 compression strokes.
ETA; I would run a tank of premium fuel, with injector/valve cleaner through it before going to the major expense of doing a valve job.
Also, most modern engines will still run with a bad valve, although not so smoothly. In the old days before fuel injection, a bad valve would cause all kinds of rough operation, esp at idle speeds and heavy load conditions.
Message edited by author 2009-07-14 22:57:41.
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07/15/2009 12:04:04 AM · #44 |
If there is a burnt valve on #2 it could misfire because the fuel/air could be pumped out on the compression stroke and there is not enough there to ignite.
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07/15/2009 12:11:36 AM · #45 |
Originally posted by MelonMusketeer:
I was a line mechanic at a Ford garage in 1970, and a 1/4 mile racing mechanic before that. I have plenty of experience with engines. If you want to find out if the compression is low on one or more cylinders here is the easy and quick way to do it.
1: Disable the spark. You can do this by pulling off the plug wires, or by removing power to the coil or coils.
2: Hold the throttle open.
3: Turn the engine over with the starter for 10 or 15 seconds and listen carefully to the rhythm of the sound.
4: If it is an even sounding purr (aside from the noise of the starter and ring gear) then everything is probably ok.
5: If it sounds uneven i/e you can hear 3 cylinders in rhythm, then the 4th one comes by much quicker, then there is one cylinder with low compression.
It's that simple.
If you don't know how the rhythm should sound, then pull out one spark plug and do it again. Listen to the rhythm. The sound of the air blowing out of the open plug will indicate the time period that the engine should be turning through 4 compression strokes. |
PLEASE do NOT do this!
This will unleash a plethora of ills that will potentially cause damage and at least, cost a fair amount of money to get the memories cleared.
You might end up buying an engine management computer if you start unhooking components and power up the system and try to run it with these components unhooked.
You simply cannot do these baseline diagnostics any more.
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07/15/2009 12:43:08 AM · #46 |
Originally posted by NikonJeb:
You got a more in-depth look at possible avenues of repair from Matt.
Listen.
You can get an accurate diagnosis without having to pull the head.
But......you have to find the right person to do so. |
Some people have to learn the hard way. I figured this is how the thread would go,
his guy might be right, but no way a tech in my shop is going to take a head off
on anything without doing the steps I presented and having a hard case to do it.
His guy doesn't have enough evidence with what was presented to us to convince me as
a shop foreman to allow that.
Matt |
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07/15/2009 01:22:12 AM · #47 |
Originally posted by MattO:
Originally posted by NikonJeb:
You got a more in-depth look at possible avenues of repair from Matt.
Listen.
You can get an accurate diagnosis without having to pull the head.
But......you have to find the right person to do so. |
Some people have to learn the hard way. I figured this is how the thread would go,
his guy might be right, but no way a tech in my shop is going to take a head off
on anything without doing the steps I presented and having a hard case to do it.
His guy doesn't have enough evidence with what was presented to us to convince me as
a shop foreman to allow that.
Matt |
I'll let you know if you are right. Do give him a small break considering you are hearing what he thinks through me who doesn't know a ton about cam lashings. It's quite possible he's done a lot more and just not told me about it. In medicine at least it's also important to know what tests are important and which are less important. We have tons of test available to us, but everybody would walk out with a $10k bill. The true expert knows how to glean the correct info from fewer tests. Of course they can be wrong, but it probably serves them in the long run.
Maybe it just needs a Johnson Rod.
Message edited by author 2009-07-15 01:44:08. |
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07/15/2009 10:10:10 AM · #48 |
Originally posted by DrAchoo:
Originally posted by MattO:
Originally posted by NikonJeb:
You got a more in-depth look at possible avenues of repair from Matt.
Listen.
You can get an accurate diagnosis without having to pull the head.
But......you have to find the right person to do so. |
Some people have to learn the hard way. I figured this is how the thread would go,
his guy might be right, but no way a tech in my shop is going to take a head off
on anything without doing the steps I presented and having a hard case to do it.
His guy doesn't have enough evidence with what was presented to us to convince me as
a shop foreman to allow that.
Matt |
I'll let you know if you are right. Do give him a small break considering you are hearing what he thinks through me who doesn't know a ton about cam lashings. It's quite possible he's done a lot more and just not told me about it. In medicine at least it's also important to know what tests are important and which are less important. We have tons of test available to us, but everybody would walk out with a $10k bill. The true expert knows how to glean the correct info from fewer tests. Of course they can be wrong, but it probably serves them in the long run.
Maybe it just needs a Johnson Rod. |
In Ford speak we are taught to do the least intrusive tests first, which usually involves the least expensive. Using a SSCC method, Symptom to System to component to cause. You never move past a step unless you know the answer to the last one. The least intrusive testing will involve the tests I used earlier to confirm which system(mechanical, fuel, ignition, or engine management) to go to next. As I stated I don't think we have conclusive evidence that we have the system pinpointed. On a three valve system or anything with a VVT, VCT, or similar system a conventional leak down system is not a definitive test.
Matt
Message edited by author 2009-07-15 10:11:57. |
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07/15/2009 11:27:29 AM · #49 |
I do appreciate the sentiment Matt. Your thinking is logical and I hope he has done an adequate job. There were probably steps before getting to the leak down test because he said the first thing he did was change the plugs and put on a new coil because of the abrasion. But when that didn't work he "worked his way down" to where he finally did the leak down test. I'm not sure what steps were done inbetween.
Like I said, I'll post the end to this story as soon as I get it. Hopefully it comes out happily ever after (minus no more than $1500). |
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07/15/2009 12:52:19 PM · #50 |
Originally posted by DrAchoo:
I do appreciate the sentiment Matt. Your thinking is logical and I hope he has done an adequate job. There were probably steps before getting to the leak down test because he said the first thing he did was change the plugs and put on a new coil because of the abrasion. But when that didn't work he "worked his way down" to where he finally did the leak down test. I'm not sure what steps were done inbetween.
Like I said, I'll post the end to this story as soon as I get it. Hopefully it comes out happily ever after (minus no more than $1500). |
Two things....the first for general reference.....when I got out of the car business because I saw the writing on the wall, I was watching the daily datastream of updates take from 30-120 minutes....this was at the Ford dealership where I worked.
There is no way the independent can either keep up with, or be privy to that level of information flow. It just will NOT happen.....at least for a couple years after, and only the most relevant of updates.......they will not see the progression.
Secondly, I *highly* recommend that you have a fairly concrete diagnosis before you give anyone the okay to tear the head off. I certainly haven't heard enough validation and testing to feel that's the next step.
Again....YMMV...
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