alc1023 Posted July 1, 2011 Share Posted July 1, 2011 My 1998 Legacy has been blinking it check engine light for a few months now. I finally got a obd2 tester and found the error codes are P0301, P0302, P0303, and P0304. I think that was "misfire detected" on cylinders 1 through 4. It runs fine. It performs like normal and get the same fuel mileage it always has. Any ideas what could be causing these error codes? Thanks for your help. Quote Link to comment Share on other sites More sharing options...
bstone Posted July 1, 2011 Share Posted July 1, 2011 When all 4 are going you either have a coil that's burning out or it just happens to be that all 4 plugs and wires are failing. Clear the codes and see if they come back. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted July 2, 2011 Share Posted July 2, 2011 since this was the first read after months of misfires it's hard to guess what this means. with multiple codes you typically clear them and see what comes back first. how many miles? have the plugs and wires ever been replaced? are they subaru wires? are the plugs NGK or some other brand? these engines do best with Subaru wires and NGK plugs, i've seen other brands cause misfires right out of the box. but if they are all giving codes then the igniter or coil pack may be bad. both easily replaced in a matter of minutes. don't fail often enough to warrant the crazy Subaru prices IMO. blinking check engine light generally means repair immediately to prevent catalytic converter damage. Quote Link to comment Share on other sites More sharing options...
alc1023 Posted July 2, 2011 Author Share Posted July 2, 2011 how many miles? have the plugs and wires ever been replaced? are they subaru wires? are the plugs NGK or some other brand? these engines do best with Subaru wires and NGK plugs, i've seen other brands cause misfires right out of the box. but if they are all giving codes then the igniter or coil pack may be bad. both easily replaced in a matter of minutes. don't fail often enough to warrant the crazy Subaru prices IMO. blinking check engine light generally means repair immediately to prevent catalytic converter damage. I will go ahead and clear them and see if they all come back at the same time. It has 196K on it. I do not know how long it has been since the plugs and wires were replaced. I am not sure about the brands of the plugs or the wires. And yes the light does blink at me. Thanks to everyone that has replied so far. Quote Link to comment Share on other sites More sharing options...
alc1023 Posted July 2, 2011 Author Share Posted July 2, 2011 I cleared the codes and started the car and ran it for a minute or so, then checked the codes again. There was no error codes. So I drove it a mile or so and checked again. Still no error codes. I expect them back soon so I will let you know. Thanks Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted July 2, 2011 Share Posted July 2, 2011 when was the last time you changed the plugs and wires?? Quote Link to comment Share on other sites More sharing options...
alc1023 Posted July 2, 2011 Author Share Posted July 2, 2011 when was the last time you changed the plugs and wires?? I never have changed them and I have had the car for just about 29k miles. Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted July 2, 2011 Share Posted July 2, 2011 so buy the NGK $2.00 plugs at the parts store and a set of Subaru wires, not cheap parts store wires. this may not fix the problem (if it is the coil) but the ones you are running don't owe you anything. Quote Link to comment Share on other sites More sharing options...
Rooster2 Posted July 2, 2011 Share Posted July 2, 2011 so buy the NGK $2.00 plugs at the parts store and a set of Subaru wires, not cheap parts store wires. this may not fix the problem (if it is the coil) but the ones you are running don't owe you anything. If you plan to replace the plugs yourself, be aware it is not an easy job. Go to "search" on this forum to read what, and how others have changed their plugs. My experience is that it took me about 3 hours to change four spark plugs. There is just so little room available to change plugs. It just takes a lot of patience to do the job. Quote Link to comment Share on other sites More sharing options...
alc1023 Posted July 8, 2011 Author Share Posted July 8, 2011 I cleared the codes and started the car and ran it for a minute or so, then checked the codes again. There was no error codes. So I drove it a mile or so and checked again. Still no error codes. I expect them back soon so I will let you know. Thanks It took over 50 miles for the errors to come back. Yesterday the light came on so I checked the error codes last night and this time it is a miss fire on only cylinders one and two. I think I will change the plugs and wires and see if that helps. Thanks everyone for your help. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 8, 2011 Share Posted July 8, 2011 If, after changing plugs and wires, the codes return - you need to do a valve adjustment, and replace the O2 sensor. Valve adjustment because one has probably never been done so you are at risk of burning an exhaust valve (should do this no matter what actually), and O2 because it can cause a lean condition - especially if it's been exposed to a lot of raw fuel from misfires and is "stuck" on the rich end of it's spectrum. If it returns again - crank posistion sensor could be faulty. This is the sensor used by the ECU to determine misfire's and which cylinder they are occuring on. GD Quote Link to comment Share on other sites More sharing options...
alc1023 Posted July 20, 2011 Author Share Posted July 20, 2011 but if they are all giving codes then the igniter or coil pack may be bad. both easily replaced in a matter of minutes. don't fail often enough to warrant the crazy Subaru prices IMO. I replaced all the spark plugs and wires. Now the error has come back again. Should I replace the igniter and coil pack both or can I do one at a time. Or should I look at something else? It is just misfiring on cylinders one and two. Quote Link to comment Share on other sites More sharing options...
jcsvx Posted January 21, 2012 Share Posted January 21, 2012 OK we have fixed this problem on three different 2.5s in the last year all three have had loose front balancers the bolts were tight but bottomed out in crank the key-way and key were worn and had to replace key on all three and new washer and shorten bolt one thread (grinder) the loose balancer causes noise and the knock sensor retards the timing until it missfires and turns on cel. Hope this fix works for you too Joe Quote Link to comment Share on other sites More sharing options...
fixingrusinc83 Posted January 22, 2012 Share Posted January 22, 2012 I have fixed over 10 of these problems on 5sp's replace or unplug nuetral safety switch ECM is going into limp mode if you shut off and restart does it run ok? Quote Link to comment Share on other sites More sharing options...
Timodon Posted January 22, 2012 Share Posted January 22, 2012 I thought JCSVX was full of it but I just took off my harmonic bal and the key was half sheared Replaced it and drove 45 miles with no problem longest drive without light in a month!!! Quote Link to comment Share on other sites More sharing options...
Timodon Posted January 22, 2012 Share Posted January 22, 2012 (edited) thanks Joe our local dealer had replaced (bad loose) timing belts in the past and thought that was what was fixing the problem but one of the Mechanics remembers having to change the key on at least one of the jobs. this may not fix all of them but it has fixed several Edited January 22, 2012 by Timodon Quote Link to comment Share on other sites More sharing options...
jcsvx Posted January 22, 2012 Share Posted January 22, 2012 Tim this also explains why replacing headgaskets has fixed some of the cars because they have to take timing belts of and why a valve adjustment can fix if they use crank pulley bolt to rotate engine. it will tighten the pulley. OH THE NON BELIEVERS Quote Link to comment Share on other sites More sharing options...
kashkn Posted August 16, 2013 Share Posted August 16, 2013 How do I look at the front ballancers? Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted August 16, 2013 Share Posted August 16, 2013 How do I look at the front ballancers? huh? a little more info please. car, model year, engine, trans, miles? what do you mean by ballancers? what do you mean by ''look at''? i already know what you mean by front. Quote Link to comment Share on other sites More sharing options...
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