Mtnrider9800 Posted December 13, 2007 Share Posted December 13, 2007 I have a 99 OBW with the 2.5 liter engine This error is that Cylinder #4 is misfiring. I have changed the plugs and wires. I have run some injector clearer through the engine. I have noticed that idle speed is about 250-300 and not that smooth. Any suggestions would be appreciated. Quote Link to comment Share on other sites More sharing options...
WAWalker Posted December 13, 2007 Share Posted December 13, 2007 How many miles on this engine? Quote Link to comment Share on other sites More sharing options...
Skip Posted December 13, 2007 Share Posted December 13, 2007 WA is on the right track. I have two simple questions to add/ask. where did you get the wires? (i.e. OEM or aftermarket) what plugs did you use? Quote Link to comment Share on other sites More sharing options...
unibrook Posted December 13, 2007 Share Posted December 13, 2007 try replacing/testing the front 02 sensor if it hasn't been changed out yet. Quote Link to comment Share on other sites More sharing options...
EVOthis Posted December 13, 2007 Share Posted December 13, 2007 I had the same problem on my 96' 2.2 and i searched high and low for the problem....i tested everything possiable...it turned out the injector connectors were swapped from cyl. 2 to cyl. 4.....just my two sense.... Quote Link to comment Share on other sites More sharing options...
Mtnrider9800 Posted December 13, 2007 Author Share Posted December 13, 2007 After market wires from Autozone and the non-platinum plugs. about 120K on the engine. Could it be a fuel filter issue? Quote Link to comment Share on other sites More sharing options...
montana105 Posted December 13, 2007 Share Posted December 13, 2007 It could actually be a spark plug and wire problem even though you just changed them-as has been posted on here numerous times OEM on these items. Quote Link to comment Share on other sites More sharing options...
WAWalker Posted December 14, 2007 Share Posted December 14, 2007 When does the misfire happen? On acceleration, or at highway speed? Can your feel the misfire when the CEL illuminates? Always start with the basics. NGK plugs and OEM wires is the place to start. If the fuel filter and/or air filter haven't been changed in the last 30k miles, they needs to be replace. If that doesn't help................ Have the valves ever been adjusted? Has there ever been any major engine work done? Valve adjustment should be preformed every 105k miles, or anytime the cylinder heads have been R&R'ed. Tight valves will cause a misfire. And if not corrected, lead to burnt valves and the need for a valve job. Quote Link to comment Share on other sites More sharing options...
Mtnrider9800 Posted January 10, 2008 Author Share Posted January 10, 2008 My CEL will turn off and then at about 70mph it will come on again. There is no noticible change in how the car is running at speed, but the idle is rough at stop lights. I have not changed anything, just been trying to notice the variables. Quote Link to comment Share on other sites More sharing options...
WAWalker Posted January 10, 2008 Share Posted January 10, 2008 My CEL will turn off and then at about 70mph it will come on again. There is no noticible change in how the car is running at speed, but the idle is rough at stop lights. I have not changed anything, just been trying to notice the variables. Mtnrider9800, You have the '99 OBW 120 some thousand miles correct? You don't have a misfire or hesitation accelerating from a stop. On Subarus, secondary brake down in the ignition is most noticable under highest engine load (accelerating form a stop usually). Still, if plugs are not NGK, and wires are not Genuine Subaru, if it were my car I woud change them. CEL illuminates at ~70mph, misfire #4 code stored. But engine seems to run fine. I my experiance this is a mechanical problem in the valve train. Not engough valve lash clearance. Exhaust valves hanging up in the guides. If the exhasut valves are hanging in the guides, the problem would come and go, and not nessasarly cause a rough idle. At idle engine runs rough. Can be many things, but in context with the misfire @ 70mph....................... Tight valves If the valves are tight, an ajustment might take car of the problem, depending on how much the car has been driven with the vlaves not properly sealing. Quote Link to comment Share on other sites More sharing options...
Mtnrider9800 Posted January 10, 2008 Author Share Posted January 10, 2008 Mtnrider9800,You have the '99 OBW 120 some thousand miles correct? You don't have a misfire or hesitation accelerating from a stop. On Subarus, secondary brake down in the ignition is most noticable under highest engine load (accelerating form a stop usually). Still, if plugs are not NGK, and wires are not Genuine Subaru, if it were my car I woud change them. CEL illuminates at ~70mph, misfire #4 code stored. But engine seems to run fine. I my experiance this is a mechanical problem in the valve train. Not engough valve lash clearance. Exhaust valves hanging up in the guides. If the exhasut valves are hanging in the guides, the problem would come and go, and not nessasarly cause a rough idle. At idle engine runs rough. Can be many things, but in context with the misfire @ 70mph....................... Tight valves If the valves are tight, an ajustment might take car of the problem, depending on how much the car has been driven with the vlaves not properly sealing. Is there a good place online to purchase the plugs and wires, or should I go to the local dealer? Quote Link to comment Share on other sites More sharing options...
WAWalker Posted January 10, 2008 Share Posted January 10, 2008 http://www.1stsubaruparts.com/ Dissclaimer: I don't think the plugs and wires are going to fix your problem. I just said if it was my car I would replace them. Quote Link to comment Share on other sites More sharing options...
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