Any mechanics here with Subaru experience?

[Xylob the Destroyer]

99 Subaru Legacy Wagon Outback
2.5L engine

For just over a year now the "CHECK ENGINE" light has been coming on randomly and staying on for random amounts of time - a few minutes, a few days, a few weeks... Also the car sometimes hesitates/stumbles when cold (as in the engine is not yet up to normal operating temp).
RTFM and it says either the emissions system is jacked or the gas cap is jacked.
This all started shortly after the car passed the state emissions test with flying colors! So I took the gas cap apart and cleaned it meticulously etc etc.
Whatever. At first I thought the light was just coming on after I gassed up so the dirty as hell seals on the cap must have been the culprit (except part of the emissions test is to check the gas cap and ensure it seals properly, but I digress). It still kept happening.
So I took it to the Subaru dealar and asked them why my damned "CHECK ENGINE" light was on. They charged me $120.00 to hook it up to their computer and told me it was a "ghost code", they cleared it and it won't be a problem again.
A week later the CE is on again. YAY! I just ignored it for the most part - or at least tried to. It was really eating at me.

Eventually I took it back to the dealer and explained the whole story to them.
They hooked it up to their computer again and then their "Lead Technician" told me that the error code means "There is a massive carbon build-up in the left head which is blocking the EGR valve. If you don't replace the heads it will ruin your engine. $3,000.00 to replace one head, $5,000.00 replace both.".
I have to call 'bullshit' on this. Where is the exact location of the "Massive Carbon Build-Up in the Head Sensor"?
I didn't have $5,000.00 to dump into this car that's only worth about that anyway (if I'm lucky!).
Not to mention that in the 2 years previous I'd dumped $4,000.00 into it first replacing the viscous coupler then replacing both of the head gaskets.
And oh by the way - if it had such a massive carbon build-up in the left head shouldn't that have been identified a few months earlier when they had the damned heads pulled off the engine?
Besides, "massive carbon build-ups" in the head don't come and go. I may not be an ASE certified mechanic, but I've got a good grasp on the basics of internal combustion engines and I understand basic physics. If there was in fact a "massive carbon build-up in the left head which is blocking the EGR valve" it wouldn't just go away for a week. Or 3 weeks. Or a month.
So I tell 'em I don't have $5K, just reset the light and then ask about the hesitation/stumbling - he tells me "that's just how it is with these cars. Most cars in fact. Cars just don't run right until their up to temperature."
Seriously? This guy is their freakin' "Lead Technician"?
So I gave them another $120.00 and went home. The CE was back on again before I got home (less than 2 miles away), but it went out the next day and stayed off for more than a week.
I guess the "massive carbon build-up" went on vacation.

Today as I was leaving work it started to hesitate/stumble again - but much worse than it ever has.
Then I heard some muffled thumping from the engine compartment. WTF? Did I just lose a belt?
Pulled over, belts good. What the hell, it's cold out - I'll let it idle for a few minutes to get warmer. The idle is cRaZy! Wildly jumping between 3000 RPM and 200 RPM. No rythm or pattern to the fluctuations, just craziness.
It eventually settles down and warms up a bit - runs fine.

Throughout this entire ordeal I have never noticed any misfires (though I do understand they can be easy not to notice), no loss in power/performance (other than the already mentioned hesitation/stumbling when cold), and no loss or change in fuel efficiency (I track my gas mileage meticulously).

Anybody know WTF is going on here?

TIA!

[stiltman]

sounds like an O2 sensor to me

[Xylob the Destroyer]

I'm leaning towards O2 sensor just because that's cheap!, but it was replaced less than 18 months ago...

[Silvas]

Coolant temp sensor could be giving an errant reading causing a flooding condition. It would help to know exactly what the code was that caused the light to come on. If it was an Emission large or very large leak, that coud be your gas cap. A small or very small leak code is probably a bad hose somewhere in the emissions system. None of those would cause a running issue, however. If it was an EGR insufficent flow code, that could be what caused the tech to think blocked EGR ports. Unless your heads were taken to a machine shop and boiled out when your head gaskets were replaced (very very unlikely), that would not have solved that particular problem and could very easily have been missed if the tech wasn't looking for that problem.

Basically it's a guessing game without knowning what trouble code was set. Try to find out and let us know. That'll go a long way to helping to solve the problem.

[olyteddy]

If the part of the earth you're located in is the US, you can go to Schuck's or Checker or whatever they call it in your part of the country and use their code reader for free. I do.

[handyguy]

Buy your own code reader, it costs half of what you pay to have it read.

[rallynavvie]

I'm assuming that is a Phase I DOHC? Or is it a Phase II SOHC? Each have their own unique issues, however there was a service bulletin for the Phase II block that replaced the head gaskets with something stronger and created a really tough engine. The DOHC was a pain and was never recalled or fixed but at least it didn't have the flaky hot-film MAF sensor the Phase II block had. The DOHC needs new gaskets to prevent an internal failure. Are you overheating a lot, especially when you come to a stop after hard driving? Ever see any bubbles or sludge in the coolant overflow? Ever smell like pancake syrup around your car?

A few things that are cheap and easy to replace on your own would be new plugs and wires (might cause hesitation), fuel filter, air filter, MAF sensor (though problems with that usually stall the engine), and coolant temp sensor. I'm hesitant to think this is an O2 sensor issue because that won't affect your idle and you'd notice smells (like rich or lean fuel smells) if the O2 sensor was bad. You also mentioned your fuel economy hasn't changed.

How many miles are on the car? If the head gaskets were never replaced I'd bet there was a failure that you've been driving on for quite a while. I had a Phase II block in my old Impreza but it had the gasket kit added and it ran nearly 60k miles with a turbo kit on it and never had issues with anything except the MAF sensor (until I replaced the ECU completely). I made sure to stay away from the DOHC plants even though everyone thought DOHC > SOHC. Not really true for the year

[deadrats]

@Xylob

first things first, just because the CE light went out for a while doesn't mean the problem just disappeared, it may have been masked by you using a different gas. in all honesty it sounds like a relatively minor problem that your dealer is trying to make into something big as a way to make a ton of money from.

you don't mention how many miles you have on the engine, but here's what i would have done:

asked the dealer exactly what codes were returned

replace the gas cap

make sure the codes don't point to a problem with the canister

replace the egr

use a fuel system additive with each fill up for the next few fill ups while using the best high grade fuel you can find

if this doesn't fix it find a reputable local mechanic to pull the codes on last time and see if it now points to something else

personally i would never spend $4000 fixing the engine (as you did over the past 2 years) nor would i even consider dropping 5 grand on a pair of new heads.

what i would do is get in touch with any number of reputable junk yards that ship across the country (i use hunt's point in the bronx, but there are a few others around the country with good reputations) that get in wrecks and salvage the engines, transmissions, etc and sell them at really good prices.

a buddy of mine had a ford contour that he could afford to replace and dealer wanted a ton of dough (as did most mechanics), we ordered him an engine from hunt's point for $400 that had 40k miles on it, found a local mechanic willing to swap it in for another $400 and he couldn't be happier. i know another guy just replaced the engine that seized on his accord with an engine from them, the engine had about 35k miles on it, total cost for parts and labor was $1200, much cheaper than having the dealer replace his engine or buying a new car.

if the car is in good shape interior and body wise, it may be your most economical way to go before you commit to new heads.

one other option is to find a local mechanic that needs the business and have him yank the heads and have them cleaned, it'll probably take about 2 days to do, the charges will stem mostly from labor (as well as gaskets), but if that subaru tech was telling the truth it would resolve the problem.

hope this helped.

[freebird73717]

I second olyteddys suggestion of going to your local autoparts store (oriellys, autozone, pepboys, etc) and have them read the codes for free. My local oriellys wont read the code for me but they will let me use their tool to do it myself. It's damn easy and free is a heck of alot better than $120. After you get the codes you can investigate for yourself what needs done.

[Xylob the Destroyer]

Thanks for the replies guys - I've been without internet for the past several days...
The "100K mile" spark plugs were replaced about 10K ago
the car has 131K
the head gaskets HAVE been replaced
no coolant in the oil
no oil in the coolant
I just heard a commercial on the radio for either AutoZone or Advance that said they will 'pull your codes for free' so I'll have to give them a check
as for Phase I or Phase II - I have no idea. would that be in the owner's manual?
never over-heats
air filter is a new K&N and was replaced about a year ago when the fuel filter was replaced (along with the plugs)
the only thing I smell around my car is burning plastic from the big-ass sheet of vinyl that got caught up on my manifold/downpipes one day in heavy traffic & I couldn't get pulled over soon enough to get it all pulled off - it's baking on nicely... (this happened AFTER all the troubles started). stinky melting plastic is pretty overpowering, but I know what it smells like when you're burning coolant in the oil as I blew the head-gasket in my VW a few years ago and I'm definitely not getting that smell
I always (99% of the time) buy gas from the same Conoco, usually at the same pump even
I did ask the dealer for exactly what codes they got - they won't give me that information.
BG40K has been added with 91 octane (that's the premium at this altitude)

BTW, the light did not come on all weekend, first thing this morning it was back...

[Xylob the Destroyer]

OK - went to AutoZone and got the codes pulled:
P0400 Exhaust Gas Recirculation Flow Malfunction
P0463 Fuel Level Sensor Circuit High Input

The first one is fairly specific, the second not so much - but could certainly be a symptom of the first.

I still don't see why the dealership automatically jumped to the conclusion of "massive carbon build-up in the head" - wouldn't it make more sense that the EGR valve is damaged/failing?

I looked into the EGR valve initially and checked a repair manual (Chilton probably?) and the description of removal kinda indicated that by taking the EGR valve off the head you risk ruining it - easier (maybe even cheaper) to replace than to repair?

AutoZone has a new EGR valve for $170.00, but from reading the repair manual I don't have the tools/facilities to replace it myself... and even though I far more mechanically inclined than most of my friends I think I'd rather pay a pro to do it right than **** it up myself for free, then have to pay a pro to fix my mess.
Shouldn't be more than an hours worth of labor, right?

[Silvas]

Alldata calls for 1.1 hours labor. Good luck finding a shop That will put your own parts on, though. It could be the EGR Valve, it could be the EGR solenoid, it could be a bad vacuum hose, it could be clogged EGR ports, it could be alot of things causing that code to set.

[Xylob the Destroyer]

yeah, those are additional reasons why I'm reluctant to do it myself.
most of the private shops are pretty good about putting in parts that you bring in yourself, but then again do I want the AutoZone generic part or do I want to go with the Subaru OEM part that the certified shop can from the local/regional parts house?

[Silvas]

Autozone is good for oil and air fresheners. Not sure what parts of the country your in, but a Bumper to Bumper, or NAPA should be somewhere near you. Even if the shop does agree to install parts you bring, don't expect them to give you any warranty. If the part goes bad, you'll have to pay them to replace it again even if the parts store warranties the part. Best to pay a little more and just let them get the parts for you.

[rallynavvie]

Autozone is good for oil and air fresheners. Not sure what parts of the country your in, but a Bumper to Bumper, or NAPA should be somewhere near you. Even if the shop does agree to install parts you bring, don't expect them to give you any warranty. If the part goes bad, you'll have to pay them to replace it again even if the parts store warranties the part. Best to pay a little more and just let them get the parts for you.

I agree. If I'm not buying OEM parts for my Subarus I go to NAPA for parts. In fact I actually bring NAPA Gold oil filters to the dealership to install when they do my oil changes (because I've become to lazy to do them myself).

[Xylob the Destroyer]

I think it's the gasket on the EGR valve?

Pulled the BPT - 'clean' but wet inside.
Pulled the EGR (dropped the top not and lost it somewhere in the engine compartment!! @$#!#$!!) and very wet inside. As in water dripped out of it. Not buckets, but I certainly didn't expect any, so some was not what I was expecting.
Pulled the gasket off and it was soaked.

I'm going to try to clean the EGR out and clean the gasket off (it's FILTHY).
None of the parts stores in town have a new gasket and can't get one for a week (WTF?!).

[aedipuss]

i'd have someone pressure test the coolant system when the vehicle is cold and the spark plugs removed. most of the symptoms point toward loose head bolts/bad head gasket/cracked head. coolant could be leaking into one cylinder as the car cools when off and causing the morning problems. the "thumping"(knocking) could be caused by non-compressible coolant in a cylinder and could lead to one piston holing or breaking a connecting rod.

[Xylob the Destroyer]

Last Saturday I:
removed the EGR valve (I can't believe I lost that damned nut!)
removed the BPT
bought 2 new nuts (8mm, 1.25 pitch BTW)
cleaned the EGR with an old toothbrush, a can of intake/manifold cleaner, and canned air (being careful not to get any cleaner on the diaphragm)
cleaned up the head where the EGR & gasket mount
cleaned up the gasket to find that it is badly deformed/warped
had the wife pick a new one up at the dealer on her way home
installed new gasket, the EGR valve, and the BPT

car did not want to start. finally turned over just as I was about to give up, stumbles, hesitates, coughs out a cloud of white smoke, smooths out...
NO CHECK ENGINE LIGHT!!


Drove around for a bit, ran some errands, took it back to AutoZone - NO CODES!

[zzyzzx]

I assume that the CEL (check engine light) never came back? Also, if the car still has the original Oxygen sensors, you might want to replace them or at least find a mail order place to get the Bossh ones cheap. I forget the name of the place where my GF mail ordered them from, someplace I've never heard of. Got the ones where you don't have to resolder the wiring harness or anything. The front one was a real pain to install, but her CEL's never came back after that, and that was just over 100,000 miles on a 2002 Forester with the same engine. Autozone reads codes for free, and usually give a printout too. You spent $240 when you could have bought the code reader yourself for a lot less or got it done at Autozone for free. At least you learned the value of not trusting your mechanic.

[Xylob the Destroyer]

CEL has never come back on. Passed the state emissions test last week with flying colors.
The O2 sensor is only about 2 years old now.
Newest problem, the gas gauge is not even close to accurate and the speedo and odo sometimes take a break and do nothing for a while...
I have no idea how fast I'm going, but at least I'm not racking up miles

I'll never own another Subaru again. THey're good cars and all, but the maintenance is ungodly expensive p.i.t.a.

[zzyzzx]

I'll never own another Subaru again. THey're good cars and all, but the maintenance is ungodly expensive p.i.t.a.

I've had to do much to my GF's 2002 Forester, and I have already reached the conclusion that the car is absolutely nothing special. Replacing O2 sensors at ~100K miles, having the CD changer go bad as well are all normal maintenance items though. The axles probabl should have lasted longer than they did, and were a big PIA to replace. The only thing that I particuarly like about the car is the external transmission filter is easy to replace, as well as the transmission fluid. Any 4WD car is going to be more expensive to maintain when compared to a FWD car. By definition a 4DW car has more stuff to break, is more sensitive to tire differences, and uses more gas. Like when you get a nail in the sidewall on a 4WD car, and you either have to find a used tire with the same amount of tread or buy 4 new tires. I'd never put up with that!

I can buy the one O2 sensor for my Escort for ~$45, and not need another one for another ~100K miles (more miles if I buy the Bosch ones). For this Subaru, and probably most newer cars, it was closer to $175-200, at mail order prices for the two O2 sensors. Tires for my Escort are much cheaper as well. Having 14" rims helps. One reason I hate newr cars is because the rims are too big and that makes the tires freakishy expensive.

[Xylob the Destroyer]

my biggest problem is the engine design - if you want/need to do ANYTHING on the engine it has to come out because it's flat "H" design means you can't get to anything on it. minimum labor fee at any local dealer is $1000 because 'we have to remove the engine to do that', regardless of what 'that' is...

[zzyzzx]

my biggest problem is the engine design - if you want/need to do ANYTHING on the engine it has to come out because it's flat "H" design means you can't get to anything on it. minimum labor fee at any local dealer is $1000 because 'we have to remove the engine to do that', regardless of what 'that' is...

I think in some cases there are workarounds to them, as per postings I have seen in some messageboards. Doesn't mean that those are easy, just maybe more DIY friendly.

[Xylob the Destroyer]

yeah, still a pita to work on though...
I love that it's AWD, but for a 4 banger I was really expecting better gas mileage, especially for a standard tranny. 21MPG is nothing special for a 4 cylinder, especially since they're advertising that the new Roos get 36!

[rallynavvie]

One thing I noticed my 99 Impreza was that it got better fuel economy after I added a bunch of performance parts and altered the engine computer. Normally making an engine faster nets you worse mileage but it was the opposite with that car. Even my current Subaru, an 05 Legacy GT, gets better mileage with an ECU change. That 99 engine is just trouble though. The newer blocks are a lot more durable (especially considering the amount of boost people are running through them these days) and you even get better mileage from them. I keep hoping Subaru brings their diesel over to the US, that would be a great car for someone who wants fuel economy and AWD. The torque from diesels lends itself well with AWD cars.

I'm on my 3rd Subaru, about to take on a 4th this summer, but I think I tend towards them just because I know their engines and mechanics so well from years of tinkering. I recommend them to friends because of how durable mine have been and how much abuse they could take on the stage roads in rally. There are some to stay away from, like the Tribeca and anything with the boxer 6.

And actually, the boxer engine is easier to work on than a V because everything is above or below the engine. The only time I ever pulled an engine from one of mine was to change out the pistons. Head gasket changes might be easier on an inline or V engine because it sits on top but everything else in the engine bay is a PITA to get to. For instance I changed an alternator on an old DSM (1G Eagle Talon TSi) and I had to remove a wheel and a radiator fan to get to it. In the Subaru it's front and center under the hood. I do hate changing plugs on these boxer engines though, but if you're not in it for performance you can just get a set of iridium plugs that'll last 50k+ miles.

[zzyzzx]

yeah, still a pita to work on though...
I love that it's AWD, but for a 4 banger I was really expecting better gas mileage, especially for a standard tranny. 21MPG is nothing special for a 4 cylinder, especially since they're advertising that the new Roos get 36!

If you care about gas mileage, do not buy any 4WD car! Get a FWD car instead.

[zzyzzx]

One thing I noticed my 99 Impreza was that it got better fuel economy after I added a bunch of performance parts and altered the engine computer.

I'm thinking that you would get a big boost in gas mileage by disconnecting the drive to the rear wheels, thereby converting it to a FWD car (that and unloading some excess weight in the process).

[Xylob the Destroyer]

not worth the loss of AWD in the winter
on the auto transmission models there is a way to electronically disable the rear wheels (supposedly for towing purposes) but it's not availabe on mine as I have a manual transmission.

[rallynavvie]

You don't own a Subaru for fuel economy, you own it for the drivetrain and durability. If you're looking for fuel economy you get a Jetta TDi. Although if Subaru brings their boxer diesel to the US soon there will be a slightly better option for fuel economy in their line. I hear the new models with CVT do pretty well for fuel economy too. I get less than 18 mpg on my Legacy, but I'm certainly not driving it with the goal of fuel economy in mind.

[Xylob the Destroyer]

You don't own a Subaru for fuel economy, you own it for the drivetrain and durability...

Too true.
I knew the added weight and mechanations of AWD combined with the relatively large (for a 4 cylinder) engine would cut fuel economy from what I was used to with a 4 cylinder (1.8 litre and 2.0 litre), but I was hoping for at least 24-25 mpg...
the 21 I'm getting is OK, but their newest commercials are promising 36!