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Subaru model list and engine configuration, U.S. specifications (As best as I can remember)

LEGACY & OUTBACK

• From 1990 to 1994 Subaru Legacy 2.2L engine, available in L, LS, LSI trim, hydraulic lifters, non interference, the LS and LSI were available with pneumatic suspension to address early ground clearance issues in the Legacy
• Turbo model or “Sport” 2.2l turbo from 1991 to 1994 (non intercooled turbo)
• Turbo discontinued in 1994 in the U.S.
• 1995 brought a redesigned body with a lower stance and the added trim level of “Outback” but the same stance as the Legacy.The 2.2l stayed mostly the same but some configurations were produced with single exhaust port cylinder heads that can be problematic, And we of course started OBD II
• Trim levels were Brighton, L, LS, LSI, Outback
• The 2.5L (DOHC) was introduced in the LS and LSI models in 1995 as an option
• 1996 brought the Legacy GT with a 2.5l engine, Legacy Outback with a 2.2l manual and a 2.5L auto transmission. The Outback has a higher stance but is still just a “trim” level of the Legacy
• The 1996 2.5l has hydraulic valve train and composite head gaskets that are like in design as the 2.2l from 1990 to 1998
• 1997 brings about mechanical valve train in the 2.2 and 2.5l and MLS (Multi Layer Shim) head gaskets in the 2.5l, these gasket tend to have some internal failures resulting in overheating, this can happen as early as 60k but on average most reach over 100k before there are any problems
• Mid year 1998 brings about a redesigned 2.2l in the Legacy which is the design the 2.5l will follow
• 2000 brings about the 2.5L (SOHC) and major overhaul of the models. While the Legacy and Outback are still the same platform they are now separate Models. This is the engine that has the famed external head gasket leak that lead to the WWP-99 campaign. While the coolant leaks were greatly slowed the gaskets can still be problematic for oil leaks and some external coolant and internal leaks as well
• Legacy 2.2l, Legacy GT 2.5l, Outback 2.5L
• 2001 adds the 3.0l H6 in the Outback models only and the VDC(vehicle dynamics control) is standard with the H6, this is a chain driven motor that if well maintained is one of Subau’s best, but if neglected will cost a lot to repair
• The 2.2l is dropped out of production in 2002, and the LL Bean comes out and is only available with the H6
• 2005 is a redesign, and the Legacy GT, and Outback XT is equipped with a intercooled 2.5l Turbo(DOHC) and available 5spd sport shift transmission.  In 2006 we get a Legacy GT Spec B with a 6 speed transmission but is very limited in production

• From 2005 to 2009 there are many refinements and new emissions control devices including the PZEV (Partial Zero Emissions Vehicle) but no major changes
• 2010 is a complete redesign of the Legacy and Outback both becoming larger in size and adding the CVT (Constantly Variable Transmission)

BAHA

Limited production vehicle based on the Outback, was equipped with either a 2.5l or 2.5l Turbo

Forester

• Limited production in 1997 2.5l DOHC
• 1998 Available only with a 2.5l DOHC
• Trim levels 1997 to 2002 L, S
• 1999 2.5l SOHC
• 2003 was a partial redesign and added the X, XS Trim levels
• 2004 on Available with a 2.5L DOHC Turbo in the XT
• Forester LL Bean has an H4
• Some partial changes from 2004 to 2008 but major re-vamp in 2009 making the vehicle larger in size and a much broader appeal
• The 1999 to present all use the same type of head gaskets that the Legacy and Outback

IMPREZA

• Introduced in 1993

Available with a 1.8l and 2.2l until the 1.8l was dropped

• The Impreza RS in 1998 had the 2.5L DOHC in 1998 and the 2.5L SOHC from 1999 to present
• Available starting in 1996 in Outback and Outback sport trim levels
• Trim levels Brighton, L, RS, Outback and Outback Sport, engine configurations varied by trim level
• In 2002 the Impreza WRX made its north American Debut with a 2.0l DOHC Turbo, Followed by the WRX STI in 2004 with a DOHC 2.5l but different from the 2.5 L in the Forester XT, In 2006 the 2.0L was dropped from production in favor of the 2.5L found in the Legacy GT, Outback XT and Forester XT
• The 2007 STI is one of the more popular models as it has a better gear set for around town driving.
• Subaru drops the sedan from the line up favoring a 5-door, only to bring it back as the WRX GT
• The 2011 STI will be available as a sedan

TRIBECA

Came out in 2006 and was redesigned in 2008 only available with the H6, The H6 has changed in size and power but is still the same platform.  This vehicle is packed with features, and has the capability of 7 passenger seating.

The Rest

• Loyale produced from 1985 to 1994 1.8l and 1.8l Turbo, variations of the platform are RX, RS, DL, GL, GL10. The Loyale was virtually unchanged from 1990 to 1994 and was really only kept around as long as it was in the early 90’s because of concerns with the low ground clearance on the Legacy models. There are many configurations of these cars, some with dual range 4wd, turbo and a differential lock
• Justy, we don’t see many of these and no one will pay us to work on them
• SVX, Dropped out of Production 1996 and some 1996 sold as 1997, only available with the 3.3l H6, this was a car well ahead of its time with a lot of unique features. Was available in either 2 or AWD with an automatic Transmission only
• Subaru XT, XT Turbo, XT6 very rare anymore. The XT6 model could be found with electronic power steering, pneumatic suspension and really was a car ahead of its time

Important Notes and tips, (with a bit of sarcasm)

• Clutches are hydraulic starting in 1997 in all 2.5l versions, cable operated in the 1.8l and 2.2l up until 2000 or so. All cable operated clutches require an adjustment from time to time. Most cable operated clutches had a hill holder, a device that makes having a manual transmission on a hill a breeze.
• The 2003 Forester brought back the hill holder but it is a hydraulic and cable operated device.
• Starting in 1999 with the SOHC 2.5l Subaru went to a dual mass type flywheel. Some of these can cause a chattering issue with the clutch.
• For any 1999 and Later SOHC models it is suggested by Subaru to add their coolant conditioner at every instance the coolant is changed.
• There is a parking light rocker switch on the steering column of every Subaru, if bumped will cause the lights to stay on.
• If your battery goes dead, or is replaced and now your lights are flashing, you have tripped your keyless entry/security system even if you didn’t know you had one. If you have a remote press the button, if not or the battery is dead try the following. There is a toggle switch taped to the keyless entry module wiring harness under the dash to the left of the steering column or if you are lucky the installing technician may have done it right and actually installed the toggle switch in the lower dash panel as is should be. Press the switch with the key on and all will be well. The good news is now that you know you have keyless entry you can purchase a remote, program it in and wahoo a new feature.
• 2000 and newer models when the security system is tripped you must turn the the key in the ignition 3 times and the annoying horn noise will stop.
• If you have a seat belt chime driving you crazy try inserting the seat belt into the buckle for, are you ready, 20 TIMES and the noise shall stop, it may take you several tries at this.
• You need to service the battery on your Subaru every year or sooner, with no exceptions.
• It really is a good idea to turn off the head lights and wipers before shutting the car off, that way they wont turn on while trying to start the Subaru in the dead of winter while the wipers are frozen to the windshield, and the battery must deal with the cold, the head lights, the wipers and the starter. Not to mention the radio, heater, seats, you get the picture. The reason your wipers are now running past the windshield is the linkage was damaged when the wiper blades were frozen against the windshield and the wiper motor tried moving them, kind of like a tongue on a frozen flag pole.
• If you want the AWD system to last you want all 4 tires to be of like tread design and depth, so yes if you have a blow out requiring a tire needs to be replaced then yes you should make sure the replacement tire matches what is already on the car. This can be done 2 ways either buy 4 tires or one tire that matches the rest and have it shaved to match. Yes this can be done, but not in a hurry typically and you should never use your space saver tire for much longer than a few miles at low speeds or you will damage the differential. This is why I never suggest you pay a premium for 100,000 mile tires on your Subaru.

• You probably dont need a flush, in fact most likely you dont, if you simply follow the maintenance guide in the owners manual you shouldn’t really need to ever flush your cooling system, or transmission fluid, how ever if you neglect your brake fluid, that may require a flush to remove moisture. You certainly dont need one at every oil change interval, regard less of what the teenager at the lube center tries to tell you.
• The “I” in the maintenance booklet does not mean “Inspect” Look closer at the bottom, in fine print it states “I” = Inspect, Replace or Correct As needed. Do not be fooled into thinking the differential and transmission fluid is good for life. The GL5 gear lube is pretty much the same stuff that has been around, well since before I can remember.
• Your Subaru Doesn’t need brake calipers replaced under normal situations, but it would prefer someone older than 18 replaced the brakes in a car you tote you family around in.
• If you dont tighten the “gas cap” it will cause the check engine light to come on. If you forget to change and check the engine oil and it runs out, the engine may start making some very loud noises before ceasing to function and the “check engine light” will never come on. If your Check engine light flashes you need to stop driving the car. There is one check engine light and many different causes of the light to come on mostly dealing with emissions control devices, but sometimes more severe.
• The ATF Temp light is kind of like the check engine light, and serious if it starts flashing and should be looked at fairly quickly.
• Many newer vehicle will have a flashing cruise control light and no cruise control function if you are ignoring a check engine light(someone is trying to get your attention).
• There truly are no instances when a check engine light will come on for maintenance. The guy that set his crack pipe down long enough to tell you this should be tarred, feathered and then forced to read the entire owners manual plus the service manual just for fun.
• Because the check engine light came on last year for a loose gas cap doesn’t mean its on for a loose gas cap this time, if it is gas cap related, after tightening the gas cap the light should turn off after a few trips in the car, if it doesn’t its not the gas cap this time, its something new that really should at a minimum be looked at and from there decide if its something “worth” repairing.
• Your Subaru, as will every other car cost you a lot more to own than any ownership study will represent.
• If you decide that changing your oil less often than 3 times a year is a good idea, because Subaru and every other Vehicle manufacture makes it confusing, or Synthetics last longer, I assure you if the engine has a major mechanical issue out of warranty Subaru probably wont participate. The Subaru branded filter for all 4 cylinder model Subaru’s are tiny little.
• If every car lasted 300,000 miles with no real repairs needed how would any car company make a profit?
• A Subaru is a great AWD vehicle with a low center of gravity that will get you to where you are going and take care of you if you are ever in an accident. Through the years Subaru has appealed to many more owners than just the Skier and Hiker with the many different models and trim levels.

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This comes up a lot both for our Local customers, and we get a lot of questions about this from afar.

The old saying a picture is worth a thousand words, I think a video with a little sound is worth many more.  I did make a mistake about the green aftermarket idlers we see in many of the online kits having double bearings, that is actually not correct, they are just a single bearing idler, which is really not the best choice you can make .  It only costs a few dollars additional to get the updated component.

Thanks for reading and watching

Justin

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The gasket pictured below resembles the Head Gasket used in the Turbo models, the Tribeca, as well as the 2^nd generation 2.2l and the updated gasket for the 1^st generation 2.5L (I know there’s a lot to follow there).

The new gasket is not interchangeable with the older model 2.5L engines.   But it proves what I have been stating all along, a MLS (Multi Layer Shim) gasket is what is needed!

Thanks for reading

Justin

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One of the things I often try to convey is that there is a major difference between in parts quality.  Your Subaru needs what is called a long life bulb or for the point of this article an H7LL in most 2005 and newer Subaru Models.

Per application in many parts catalogues it will call for an H7.   Subaru recognized the standard bulb wasn’t up to the task and superseded the part to another part number indicating a Long Life bulb part number 84920 AG020.  The H7LL bulb has a much stronger element that will last longer than the standard H7 bulb, yes it is a little more expensive but only a few dollars.

In the pictures below, I have tried to point out how it’s nearly impossible to look at the bulb and see a difference but on the Box itself there is a different part and catalogue number.

As always it’s up to you the owner of your car to know what is being used in the care and service of your Subaru, I will try to point out trends as I can to help you along the way.

Thanks for reading

Justin

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Nowhere is this more obvious than their oil filters and how they have changed, superseded and morphed through the last few years.

The O.E. oil filter you buy for your older model Subaru today looks nothing like the one it came with or was installed for years, but in Subaru’s quest to keep things simple they have decided to not make available the older oil filters, but instead have shrank the size of the filter and dropped the older part numbers from production and inventory.

Pictured below are the last 3 oil filters used by Subaru for the 4 cylinder model.  The black one in the middle was first used on the 2002 WRX turbo models, the reason for this is the Turbo models exhaust system runs very close to the oil filter and it was necessary to shrink the filter down to keep the oil filter from getting to hot and thus increasing the oil and engine temperature.   Here is where things have gone from there, we used to install the black filter on the turbo models, the white filter on everything else except for the H6 and the Loyale.   Then Subaru dropped the white filter from production, but wait a minute any one can see the white filter is bigger!   The oil filter now used by Subaru on all 4 cylinder models is the blue one, which is even a little smaller than the black one and yes still much smaller than the white one that was used on your non Turbo model Subaru for years. I also want to point out the location on the engine for the oil filter on the 4 cylinder Subaru models has not changed since the Legacy came out in 1989.

If you own a Turbo model Subaru and don’t change your oil and filter at least every 4,000 miles you will most likely buy a Turbo or worse an engine, this is the current theme in the 2005 and newer Legacy GT, Forester XT and Outback XT models.

Before there is any argument about synthetic oil and oil analysis, the oil filter used by Subaru is very small and will not last the 7,000 miles your synthetic  oil may last, oil analysis has no way of catching the slow clogging of the oil feed line to the turbo.  Damage from extending the oil changes can happen very gradually over time or can ruin your trip in mere seconds and be very costly.

If you change your oil twice a year versus 3 to 4 times a year you will save roughly $800.00 over a ten year period.  The bad news is you will most likely buy a Turbo and the Turbo will cost over $1200.00, just for the part!  Add to that labor, gaskets and the possibility of the Turbo damaging the Engine just for fun.

If you own a older model Subaru (pre 2005) and the dealer is now installing the blue filter you are now cutting the filtering capacity and oil capacity down from how it was originally designed, and if you exceed the ability of the filter to filter, it doesn’t filter and contaminants in the oil will circulate around in the oil rather than be caught in the filter, this is done as the filter becomes restricted by the bypass to protect the engine from ever being starved for engine oil.

Subaru changed the exhaust lay out of the header pipe in all of their four cylinder models to resemble the Turbo models and now all of the 4 cylinder models have the exhaust system running very close to the oil filter rather than on the turbo models.   So all current production models get the small oil filter as such there is no need for Subaru to keep making available the bigger oil filter even if it would be more beneficial to your 2004 Outback or your 1992 Legacy.

At our shop we use the Blue filters on cars still covered under A Subaru warranty to just keep things simple, and try to explain that the ramifications of going to long with the little blue filter won’t show up until the car is out of Warranty and its all your car.  We install a large oil filter on models that don’t have a turbo or newer exhaust system.  For turbo and 05 and later models we use a filter closer in design to the black filter as the Blue filter leaves a lot to be desired and anyone (minus the engineer who designed it) when holding the blue and black filters in their hands side by side will agree the quality of the filter is just not the same as it used to be.

The good news is Subaru did lower the price of the blue filter a little.

When I see things like this I will always try to find a solution to deliver more value than just going along with a corporations desire to cut costs.  While I will also never claim to be as clever as the engineers, I will also never lose the argument that reducing oil capacity and filtering capacity is a bad idea.  I kind of seriously doubt accounting ever consulted the engineers anyways.

Thanks for reading

Justin

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Things to look at on your Subaru now that the leaves are starting to turn color are as follows.

The engine oil level and condition should be inspected, if it has been longer than a few months since it has been changed now is the time.

Engine coolant should be inspected for level, proper freeze protection and for any signs of contamination.

The wiper blades should be checked for streaking, tears and cracks.  Windshield washer fluid should be checked for level and freeze protection as well.

Tires should be checked for the proper pressure, wear, punctures (screws and nails) and for weather checking this is also a good time to consider rotating and balancing the tires as well.

All of the lights should be checked for proper function and the head light lenses inspected for any signs of dulling or pitting as this can be corrected and greatly improve night time visibility.

If the Subaru is due for any maintenance such as the transmission fluid or differential fluids being serviced now is the time, as starting out the cold part of the year with fresh fluids will go a long way in protecting the devices the fluids are intended to lubricate.

The coolant hoses and accessory drive belts should be inspected and replaced if the hoses feel soft or crunchy, or if the belts are cracked or frayed.

This is a good time to inspect the spare tire, vehicle jack and lug wrench, a flat spare tire really won’t do you much good.

The battery should be serviced and tested; the charging and starting systems looked at as well including the battery cables.

These are just a few examples of ways to get your Subaru ready for fall and winter; a little preventative maintenance can go a long way towards a trouble free Fall and Winter driving season.

Thanks for reading

Justin

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Ken will be there, camping out, taking pictures and handing out goodies here and there.

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If you haven’t already read the post your Subaru check engine light explained I would encourage you to, as I am only going to try and cover things not already talked about or will be expanding on the previous article.

I have received a lot of comments about the previous post and as I answer Question under Subaru Repair on all experts everyday as well as talking to our local customers.  I have a good feel for what is going through the minds of many Subaru owners wherever they may live. 

The first thing I really want to stress here is that a good thorough analysis of a codes set in regards to a check engine light is always better than plugging in a code reader at a parts house. You can go to the doctor and have your blood pressure checked and they can inform you it’s high, here are some pills or you can have further tests done to determine the cause of the condition and any symptoms.   Knowing the code set in the ECM’s (Engine Control Module) memory is like knowing you have a fever, when why is the answer that is needed.  The choice is really yours to make and a cheap or free check engine light scan does not necessarily equal value.  There is the old saying you get what you pay for.  

Next there are hundreds of possible codes, thousands of possibilities and only one light, can you imagine an airplane having one light for all of its many engine management systems?  There should be a check engine light pertaining to the engine, its sensors and control devices necessary for proper engine function and another light for Emissions control devices and the systems that monitor those devices.  But that is not the system we have nor does it appear that this is going to change anytime soon.

It is far more complicated than most understand, any many cars go without ever being properly diagnosed and repaired.  The biggest area of confusion is that some believe the light comes on at a preset interval, but the reality is there is no check engine light on your 1996 and newer Subaru that comes on at a predetermined mileage or time frame. The second is that some times the light will go on and off for months as a result of programming, monitors, drive cycle events, temperature and the nature of electricity.  Most of the time the car will seem to run ok and that is a result of what is called adaptive strategy, this is the ability of the ECM to overcome faulty sensors, intake leaks and even some misfires.   

I would say that less than 35% of the industry actually understands how an OBDII system actually works and I guarantee you that not one person behind a parts counter with a code reader understands what a catalyst monitor is and what are the parameters of the monitoring system.  So why should they give any advice at all in regards to a check engine light, is there any value in there opinion?   In the portion of states that have a vehicle emissions programs the Technicians that are licensed by the state to diagnose and repair emission related problems are a leg up on Technicians that are not required to maintain there license and thus their education.

The Check Engine light is more about the Emissions systems on the car then it is the actual engine itself.  If the Technician working on the car is not an Authorized Emissions Specialist he or she may not have received the proper training or is defiantly not going to be as up to date as a Technician that is staying current.  I often find that when I talk to my customers about what is truly involved in the diagnoses and drive cycle after repair, most had no idea just how complicated it can be to truly diagnose, repair and than verify that repair.  

The check engine light comes on and a code is stored in the computers memory, the engine may or may not feel any different.  this is really where the confusion starts.  A loose gas cap can cause a “check engine light” but what on earth does the gas cap have to do with the engine?   I wish there were two lights and two legs to the the system one being a check engine light and the other being the check emissions light.  But the federal government was afraid of creating confusion with multiple systems, yes in 1996 The government decided we needed a standardized system. I agree that we needed some standardization , but the intent was to clean up the air and this attempt has largely failed.  The single biggest problem is lack of enforcement.  I hear so often that a Dealership told a driver the light was no big deal when the real secret is there are a lot of items on a newer car that are under warranty for a much longer period of time than most drivers are aware of.  Or I hear about a check engine light being on for three years with only maybe some confused partial attempt at repairs usually done by scanning it at the local parts store and installing one or two suspected “bad ” parts.      But there is only one light and there is no way to know if the check engine  light is on because of a loose gas cap or a failed coolant temperature sensor without a proper diagnoses  or at a minimum a code scan, one will let excessive hydrocarbons into the atmosphere in the way of raw fuel vapor and the other may leave you stranded.  

Here are some tips for 1996 and newer Subaru vehicles that will hopefully help.

On the dashboard of your car there are many different colors of light.  Lets break down the different colors and what they each mean. The turn signals are green and just like a traffic signal green means go.  The check engine light, ATF temperature light are yellow and yellow means proceed with caution.  The oil light & battery light are red and mean stop driving the car.  The additional aspect of the check engine and transmission temperature lights is the ability to flash which is basically an indication to stop driving the car.   If your check engine light starts flashing you need to have the car looked at as soon as possible.  

Consider purchasing a basic code scanner yourself if you have a diagnosed emissions related problem that you cannot afford to repair.  For example a Catalyst system may cost upwards of $1200.00 to repair and that could be a hard pill to swallow.  But since there is only one light how will you know if anything comes up? This is when I suggest a basic code scanner, if something new comes up on a weekly or biweekly scan you will know to have it diagnosed.   Keep in mind a code is only the starting point.

There are two different types of codes component and conditional codes, here are some of the most common codes we deal with and the process that needs to be done to truly get to the bottom of the code.

P0440 Evaporative emissions leak.  The ECM monitors the Evaporative system pressure and through the monitoring system believes there to be low or no pressure, the most common cause is a loose gas cap but a leak any where else in the system can cause this as well, typically a smoke generation machine is used to look for leaks in the Evaporative Emissions system A smoke machine can cost over $1000.00 and has on going cost in the way of the what ever is used to create the smoke such as mineral oil.  So why on one hand a loose gas cap is pretty easy to figure out, connecting a smoke machine to the proper ports in the Evaporative Emissions system then look for leaks, the Evaporative system runs from the fuel tank to the engine compartment stopping at the purge canister, vent solenoid and other components as well.  If no leaks are found there are other possibilities such as electronics not turning on or off as they should.  This could be anything from a failed solenoid, faulty wiring or problem with the vehicles computer. 

P0420 Catalyst efficiency below threshold.  My favorite, Here is why the code is set.  Starting in 1996 every vehicle for sale in the U.S. had to have a way of monitoring Catalyst function.  The job of the Catalytic Converter is to take Carbon Monoxide (a by product of internal combustion) and convert some of it back to Oxygen, this is done with three precious metals, temperature & fuel mixture.  There is an Oxygen Sensor, or O2 sensor mounted in front of the Catalyst and one after.  The ECM (Engine Control Module) uses data from the O2 sensors to know if the Catalyst is doing its job of creating Oxygen.  Now the ECM does not constantly monitor the Catalyst system, this starts to get a bit complicated but depending on how the vehicle is being driven it is not always possible for the Catalyst to function properly as such in the ECM’s programming it will only monitor the Catalyst function after certain events have been met in a drive cycle.  Once the ECM is looking at Catalyst it uses the voltage values created by the front and rear O2 sensors to determine if the Catalyst is working with in the programmed threshold.  there are a couple of ways to properly test a Catalyst, but the most accurate way is to do a Catalytic Converter efficiency test.  This test involves running the vehicle until it is up to temperature, then install a 4 or 5 gas analyzer probe into the tail pipe of the exhaust, then shutting the vehicle off, disabling spark and fuel (to keep the vehicle from starting), injecting propane into the intake manifold, and cranking the vehicle over and obtaining the readings from the gas analyzer.  The reason for the test procedure is to remove the ECM, Mixture and O2 sensors from the loop, to purely test the Catalyst’s ability to function and it is a pass or fail test with a few Grey areas.  It is not possible to simulate this test with a generic scan tool in the Auto parts store parking lot.  A failed Catalyst is just one of many possible causes of this code and at the time of writing this article the list price for a one piece Catalytic Converter (found in most 1999 to 2004 models) from Subaru was $974.00 not including labor or gaskets.  If the Catalyst is not the cause which is very possible and the culprit is a O2 sensor there are other possible ramifications of not repairing the vehicle properly. If the Catalyst has failed, reasons as to why need to be investigated to avoid a quick repeat of the failure.  The number one cause we see at the shop is a failed head gasket allowing coolant into the exhaust and degrading the Catalytic Converter and or 02 sensors.  But we have also seen contaminated  gas, slow O2 sensors, and Mixture problems cause this as well.  You have to remember the Catalyst function is measured by the ECM as seen through the “eyes” of the O2 sensors.  If you live in Washington State and fail an Emissions test as a result of a check engine light and a PO420 code set, you can request they perform a tail pipe test and if it passes so should your car.  Why is this?  There is chatter that there is a disconnect in some cases between oxygen content in the exhaust and cars that will still run below the legal “measured” tail pipe Emissions standards for that year. 

In Washington state there is a limit an owner has to pay to obtain a waiver in lieu of making a vehicle pass the test and the vehicle is tested every 2 years.  The repair waiver is is granted as long as repairs and or diagnoses are done in the attempt of making the vehicle pass and this work is done by an authorized Washington state department of ecology emissions specialist.  This only applies to unmodified vehicles and is up to the state to decide if you qualify.  Other states have similar programs, and you should check the department of ecology website for the state you reside in for current information. 

P0301, P0302, P0303, P0304, Cylinders 1 through 4 misfire also usually a flashing check engine light will occur as well.  On a second generation Subaru Engine the most common cause would be spark plug tube seals that have allowed oil onto the spark plug wires and plugs, but we also see a fair amount of failed coils, plug wires, spark plugs and some models with an injector failure.  From there a burnt valve, broken ring, rodent chewed wiring and gasket leaks are all examples of things that can cause a misfire code as well.  A flashing check engine light really means you should not drive the car as damage can occur to the Catalyst, rod bearings, head gaskets and the list goes on. 

So one day the light comes on and the gas cap is found loose, but the next time the light comes on tightening the gas cap doesn’t fix it.  Frustrated vehicle owners take cars in to have the check engine light  repaired and it is, for a couple of months but then comes on again.  The owner than takes the car back to the shop where the service advisor, owner  or Technician has the task of trying to explain that most likely its just a new problem.  This is a very common situation that happens and there are a wide variety of reasons as to why this happens.  This is one of the single biggest reasons you should have a place you take your car to for all your service needs.  Taking it to shop A and then to shop B three months later will typically not yield the best results.  If you have lost confidence in a shop on a repeated check engine light situation that is understandable.  A good repair shop will document what codes are set each time the car comes in what was done to diagnose and or repair the condition if it is a different code each time it is most likely a different issue each time.  If there is an ongoing issue keeping one shop involved is a better way to go in most cases.   There are always exceptions to this and only works if the shop you are taking your car too is familiar with the brand.  Sometimes it takes a significant amount of time to diagnose certain conditions that may trigger a check engine light.  A general repair shop is going to have a disadvantage in some cases over a specialist in one make of vehicle.  As we specialize in Subaru we have a huge advantage over the shop down the street that works on every type car that comes in.  Dealership service departments are all about profit and productivity and are generally a bad choice for a problem child that will take a lot of time to get to the bottom of, its just not what they are good at. 

Auto repair is not an exact science, sometimes a good diagnoses is a process of elimination and can be very time consuming as well as frustrating for both driver and shop alike, but it doesn’t have to be that way, a better understanding about how the systems actually work can go along way to clearing up confusion.

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