Cylinder misfire CEL

[xt2005bonbon]

about 6 hours yesterday, but that included prepping my work space a bit (my buddy was kind enough to loan me his garage) and about the same today, with putting it on the truck and reattaching the hood, etc. Not the world record for sure, but I'm glad it's out. Getting it in will be a whole different challenge.

 

Good job man. So you did it by yourself then ?

 

We do have to recall that your compression and leakdown tests turned out good. So, what happened to your engine is weird. Curious to find out what is really wrong with it..

[deltasierrahotel]

I wasn't alone. I had help on Saturday with the pull.

[Genesis_Beast]

Hey everyone.

 

Im currently owning and drving a MY06 3.0RB sedan Liberty and after reading this thread, keen to ask for some advice.

 

Ive been getting a CEL coupled with the cruise control disabled. The code ive been getting is a missfire on the drivers side bank of the 6 cylinder (So 1 3 and 5 cylinders)

 

Any suggestions? after reading the Problems with the 4 cylinder variants, my mechanic has changed all 6 sparkplugs, swapped coil packs. after reading here, im going to see about replacing the injectors.

 

The code comes and goes, usually on a leisurely drive. after a few kilometers and several stops (turning off engine for a period of time) and getting in, the CEL is gone and goes about its business, then few days later comes back mid drive, not hard driving or anything.

 

 

My mechanic isnt a subaru mechanic, but is a very good private one. He thinks that the CO2 sensors are fine, plus the air intake. Ive had a head gasket change about 2 years ago, And has thrown his hands up and said the the computer needs to be checked/ scanned and thats all that it could be. Ive read about lack of Fuel delivery, not strong enough?

 

 

any help could be appreciated

[deltasierrahotel]

We do have to recall that your compression and leakdown tests turned out good. So, what happened to your engine is weird. Curious to find out what is really wrong with it..

 

Yeah, I'm curious as well. The guy I took it to said he should have it apart by the end of the week. Being that the car was rapidly becoming undriveable and I was out of other ideas, I figured pulling the head of the 2&4 side was the only way to find out what's really wrong and I decided to move ahead. I would have liked to have a second opinion from Rallispec, but I didn't feel good about driving the car to Jersey in it's current state (not that I ever feel good about driving to Jersey, even in the best circumstances ). Also, Dave at Rallispec told me he suspects a bad valve or ringland when I gave him my sob story over the phone.

 

I'll keep you posted.

[xt2005bonbon]

^ thanks for the feedback. In a way, I am actually really impatient to find out what's wrong with your engine.

My car is doing OK though I just drove it 15 miles in 10 days.. Tomorrow is D day for me. That'd be funny though if I get good results like you. In any case, I still have to change my IM o-rings.

[deltasierrahotel]

Well, if I don't have a valve or ringland problem I'm gonna be bewildered and clueless as to what steps to take next. I'll post an update as soon as I know.

[ScottFW]

Hey everyone.

 

Im currently owning and drving a MY06 3.0RB sedan Liberty and after reading this thread, keen to ask for some advice.

 

Ive been getting a CEL coupled with the cruise control disabled. The code ive been getting is a missfire on the drivers side bank of the 6 cylinder (So 1 3 and 5 cylinders)

 

Any suggestions? after reading the Problems with the 4 cylinder variants, my mechanic has changed all 6 sparkplugs, swapped coil packs. after reading here, im going to see about replacing the injectors.

You said the code was for one bank. Could you not localize the trouble code to one particular cylinder? I'm not familiar with the 3.0, but the codes on the 4-cyl will tell you which cyl is misfiring. How's your idle? Smooth or bumpy/rough? It looks like the Australian 2006 Liberty 3.0R is supported by Romraider, so with a vag-com cable and some free software you might be able to log cylinder-specific problems yourself.

 

If it's just one cylinder, it's either rings or valves on that cylinder, or the plug, coil, or injector. Can you look at your long-term fuel trims with Learning View or Romraider? If one injector isn't flowing well, the O2 sensor will see leanness and richen up the fuel trims to compensate, so that could be one clue. Take note of the fuel trims before clearing any misfire codes from the ECM, because clearing the codes also resets the fuel trims.

 

I would try to diagnose as much as you can with the available logging software. Injectors are a little pricey to replace just for the hell of it, so I'd want solid evidence they're at fault before doing that. Cleaning is cheaper than replacement, but will involve some downtime if you don't have a place that can do it locally.

[Genesis_Beast]

Hey scottFW

 

 

Thanks for the advice mate! much appreciated. The codes come up with saying that 1, 3 and 5 missifre. so all 3? im unsure if that means its a specific cylinder.

 

My Mechanic isnt a subaru dealer, but has owned a few subarus in his time. My Mechanic uses a form of Dianotisc tool off handheld device, i forget the exact name. He tried swaping the coil packs, which are conected to each bank (left and right im assuming) When changing all 6 spark plugs, he swapped the packs over so right on left and left on right and said that if you get the CEL, come back, we'll scan it and see if its the coils, becasue the codes would say 2,4,6 cylinders instead.

 

Its still happening, after fresh plugs, swapped coils, front O2 sensor checked, the airflow meter cleaned nothing seems to be working, the only thing now is checking the computer or injectors?

 

The Idle on the car when just starting up is a little jerky, but when its warm and at operating temp, it ticks over nicely, bar a few bumps/jerks on occasion, you can feel them occcasionally. The CEL and cruise control flashing, comes on for a few hours/ maybe over a day, then clears itself, then comes back on whilst leisurely driving.

 

Im up in arms about it and total over it. Is the Romraider a computer program that could be used on a laptop and i just vag-com cable?

[deltasierrahotel]

^ thanks for the feedback. In a way, I am actually really impatient to find out what's wrong with your engine.

 

Well, the time has come! The mechanic pulled the heads off my engine yesterday and I have a bad exhaust valve on my fourth cylinder. It's sucked down too far and there isn't proper clearance between the valve and the cam.

 

He's also gonna pull the pistons, make sure the ringlands are good and he'll re-ring the pistons, so when I get it back it will be almost like new.

[xt2005bonbon]

Wow. That's crazy. Well, you should then get a tune afterwards so as to avoid burning another exhaust valve.

 

So you are not planning to get a new short block then?

 

BTW, I see that you have a manual trans just like I do. I don't know if you've heard of the tsk3 kit for your clutch. It is an important 'mod' to do while the engine is out.

 

Here is a link description:http://www.infamousperformance.net/servlet/the-107/Subaru-Tranquil-TSK3-Sleeve/Detail

 

Another one is to change the OEM oil pick up tube. You can use a killerb for instance.

 

Last mod I've heard people encouraging us to do is to change the OEM oil supply lines with a kit from Infamous.

 

Those are the bare minimum mods I'd do that come to mind.

[Indiglow]

he burned a valve not because of the tune but because his valve lash was too tight, which higher mileage subarus tend to do since subaru sets the lash on the borderline tight range from the factory. they do this because they are quieter when tight rather than loose. a valve lash which is too tight will cause the exhaust valve to not completely close and contact the head, and to not contact the head for a long enough period of time. the contacting of the valve to the head absorbs head from the valve. when it doesn't contact enough it will eventually burn up.

[xt2005bonbon]

he burned a valve not because of the tune but because his valve lash was too tight, which higher mileage subarus tend to do since subaru sets the lash on the borderline tight range from the factory. they do this because they are quieter when tight rather than loose. a valve lash which is too tight will cause the exhaust valve to not completely close and contact the head, and to not contact the head for a long enough period of time. the contacting of the valve to the head absorbs head from the valve. when it doesn't contact enough it will eventually burn up.

 

What you say also makes sense. But I was going of the following info:

 

It's not the valves that are the problem, it's the factory tune. It is well known that the OEM map has a flaw and can cause burnt valves.

 

http://legacygt.com/forums/showthread.php/dangerous-cylinder-trims-5th-gen-lgts-193842.html

 

 

 

That's from my Tuner, he found the flaw a few years back.

[Indiglow]

The tune may contribute a little bit, but this issue does not only occur in subarus. valve lash that is too tight from wear will ultimately burn up the valve itself. typically the oem tune runs a lot of low load timing and avcs advance to improve efficiency, and on boost runs richer than necessary. also, ignition timing, if dips too low, will cause increased egt's and exh valve damage over time. typically I've seen this in cobb ots maps where at full load timing is ~10*, sometimes lower if you have any mechanical quirks. the combination of these issues will ensure a burnt valve.

 

you can remove the valve cover and check the lash of each valve. This is just the nature of subaru and their factory preference in what the specs are when the engine is built. I whole-heartedly believe that this is why they burn exhaust valves, it's not simply because of the tune, and not one person "found" the flaw in the map as any tuner who knows how to use an ECU will be able to see what kind of "damage" the engine would experience based on the parameter tables. and yes I am aware of nonlinear fueling on the oem map but nothing that strikes me as a post-TDC risk since there's a decent rich dip. the oem tune doesn't necessarily help the cause, but, certainly isn't the primary cause of burned valves, plain and simple.

 

if you pull a motor from a 100k mi turbo subaru, you're bound to find a bucket to be riding on the cam lobe with zero clearance. it's not uncommon, but it's the nature of subaru head wear along with the factory lash specs, they just seem to wear enough with enough tight clearance to end up causing issues it in not-too-long of a period.

 

Most subaru shops when rebuilding will set clearance on the looser end of the spec range(per subaru), this causes the valves to be a little louder in operation but ensures the valve is contacting the aluminum head for longer and staying cooler. some say this might impact fuel efficiency and maybe power but according to engine builders and post pro dyno tuning, the difference is extremely nominal if any.

[xt2005bonbon]

^ thanks for your insights.

[deltasierrahotel]

Wow. That's crazy. Well, you should then get a tune afterwards so as to avoid burning another exhaust valve.

 

So you are not planning to get a new short block then?

 

BTW, I see that you have a manual trans just like I do. I don't know if you've heard of the tsk3 kit for your clutch. It is an important 'mod' to do while the engine is out.

 

Here is a link description:http://www.infamousperformance.net/servlet/the-107/Subaru-Tranquil-TSK3-Sleeve/Detail

 

Another one is to change the OEM oil pick up tube. You can use a killerb for instance.

 

Last mod I've heard people encouraging us to do is to change the OEM oil supply lines with a kit from Infamous.

 

Those are the bare minimum mods I'd do that come to mind.

 

Thanks.

 

I'm planning on using AccessPort after I get everything back together and I'm sure things are running well.

 

I'm not planning on replacing the short block. That's another two grand and this repair is already costing much more than I was planning on putting into the car this year. Is there some reason the short block shouldn't be good for the life of the car?

 

I just got a new clutch a couple hundred miles ago. Is installing the TSK3 kit easy if I'm not doing a new clutch but have the engine pulled? It would be nice if this TOB lasted a good long time. (As a side note--The original TOB went 94k before failing and the clutch was in pretty good shape when it was replaced, but other members seem to be replacing clutches every 50-70k miles. I've only had the car for a year, so maybe the previous owner drove all highway miles. And maybe I was just spoiled by the clutch on my 94 Accord going 194k before being replaced, but 50k miles doesn't seem like a very long time, unless you're racing or something.)

 

What's the advantage of aftermarket oil pick up tube and oil supply lines? Do the stock ones have an issue?

 

Thanks for your input.

[xt2005bonbon]

I'm planning on using AccessPort after I get everything back together and I'm sure things are running well.

 

^That's what I plan as well: run the car on stock tune for a little while to make sure she's running well. Then I'll get a tune.

 

 

I'm not planning on replacing the short block. That's another two grand and this repair is already costing much more than I was planning on putting into the car this year. Is there some reason the short block shouldn't be good for the life of the car?

 

^Some others may chime in on this. I do not have a specific preference right now. Just that I've seen most people taking this route when they are having any significant issue related to the block (like broken ringland,etc..). But I guess you don't.

 

I just got a new clutch a couple hundred miles ago. Is installing the TSK3 kit easy if I'm not doing a new clutch but have the engine pulled? It would be nice if this TOB lasted a good long time. (As a side note--The original TOB went 94k before failing and the clutch was in pretty good shape when it was replaced, but other members seem to be replacing clutches every 50-70k miles. I've only had the car for a year, so maybe the previous owner drove all highway miles. And maybe I was just spoiled by the clutch on my 94 Accord going 194k before being replaced, but 50k miles doesn't seem like a very long time, unless you're racing or something.)

 

^I am not sure if you can install the kit without removing the clutch.

 

 

What's the advantage of aftermarket oil pick up tube and oil supply lines? Do the stock ones have an issue?

 

Here are a couple of threads related to this issue. Essentially, the OEM oil pick up tube is known to fail without warning until it is too late. It usually cracks at a very specific location. On the killerb website, you can read their theory as to why it cracks.

 

http://legacygt.com/forums/showthread.php/oil-pickup-tube-failures-important-78603.html?t=78603&highlight=oil+light+flickers

 

http://legacygt.com/forums/showthread.php/oil-pick-up-failure-123825.html?t=123825&highlight=oil+light+pick

[Max Capacity]

If your pulling the engine, the TSK3 kit will be easy to install on the tranny snout.

 

Grease the snout and the end of the input shaft where it goes into the pilot bearing.

[xt2005bonbon]

How much will it cost you so far?

[deltasierrahotel]

So far this year I spent $1,600 on a new clutch and axle install and I'm anticipating this engine debacle running $1,800 to $2,500 with the (extremely) discounted labor I'm receiving, parts and machine shop fees. I saved some money pulling and reinstalling the engine myself. AccessPort will be another $400-$600, depending if I get it new or used. (Not that AP is a necessity, but...)

 

So between four and five grand, I'm guessing. That's if I value my time at $0/hr Not that I mind spending time working on my car, it's kind of fun, as long as things go smoothly. I just don't have much more money to throw at this right now. I bought the car a year ago for $11k, I was planning on being much closer to paid off before I put this kind of money into it. But what is it they say over there, c'est la vie?

[deltasierrahotel]

on the upside, I was due for a timing belt and tensioner pretty soon anyway, so this eliminates the need to do that separately.

[Max Capacity]

FWIW, here's my thread for reference.

 

http://legacygt.com/forums/showthread.php/got-some-new-stuff-engine-r-r-184106.html

[deltasierrahotel]

My LGT is an 05. Is there a way to tell from my VIN if I have an older oil pick up tube that doesn't need to be replaced?

[ehsnils]

Thanks.

 

I'm planning on using AccessPort after I get everything back together and I'm sure things are running well.

 

I'm not planning on replacing the short block. That's another two grand and this repair is already costing much more than I was planning on putting into the car this year. Is there some reason the short block shouldn't be good for the life of the car?

 

I just got a new clutch a couple hundred miles ago. Is installing the TSK3 kit easy if I'm not doing a new clutch but have the engine pulled? It would be nice if this TOB lasted a good long time. (As a side note--The original TOB went 94k before failing and the clutch was in pretty good shape when it was replaced, but other members seem to be replacing clutches every 50-70k miles. I've only had the car for a year, so maybe the previous owner drove all highway miles. And maybe I was just spoiled by the clutch on my 94 Accord going 194k before being replaced, but 50k miles doesn't seem like a very long time, unless you're racing or something.)

 

What's the advantage of aftermarket oil pick up tube and oil supply lines? Do the stock ones have an issue?

 

Thanks for your input.

 

The stock oil pickup tube is one of the causes for blown engines. It cracks by the brazing at the flange where it's connected to the pump and then the engine loses lubrication.

 

It doesn't happen to everyone, but has happened often enough to worry about it.

[deltasierrahotel]

Thanks.

 

MaxCapacity indicated here that maybe it isn't a problem in 05s, or at least some 05s.

"Mine is a early 05 so I don't think anyone has had a problem with the tube cracking with early 05's."

 

Is there a way to tell based on my VIN?

[xt2005bonbon]

I was planning on being much closer to paid off before I put this kind of money into it. But what is it they say over there, c'est la vie?

 

 

AccessPort will be another $400-$600, depending if I get it new or used. (Not that AP is a necessity, but...)

 

^I will be doing an etune. You get a VAGCOM cable for like 15-25 bucks and the tune costs around 150 bucks. You could save a bit if you were to go that route. I am still a noob at this tuning business but I'll get the hang of it pretty quick I believe. All the info on how to go about it can be found in the tuning section of the forum.

 

The stock oil pickup tube is one of the causes for blown engines. It cracks by the brazing at the flange where it's connected to the pump and then the engine loses lubrication.

 

It doesn't happen to everyone, but has happened often enough to worry about it.

 

^+1.