don80 Posted October 15, 2005 Share Posted October 15, 2005 My 99 forester with 2.5 (115000 miles)is making this nagging engine knock once i get up around 3KRPM. it's not there cold but gets there when it warms up and remains even in idle. Once cooled down with engine off it goes away once again until warmed up and driving. I guess it could be a plugged valve lifter if this model has them . Sounds more knocky then tappy like i would expect a lifter. Link to comment Share on other sites More sharing options...
nipper Posted October 15, 2005 Share Posted October 15, 2005 This does not sound good. It almost sounds like a rod knock. Has the car ever been overheated? You can try this. when the car is warm and running, dissconnect one spark plug wire at a time. If the sound changes pitch, you found its location. If it doesnt go away we can rule out rod knock. nipper Link to comment Share on other sites More sharing options...
cookie Posted October 15, 2005 Share Posted October 15, 2005 seriously though thats not so good. I thought my 99 Forester had haydraulic lifters but one of the folks here told me it was mechanical. I've never had a problem so I have not looked. I'd start by pulling plug wires to see if I could isolate it to one cylinder if a valve lifter adjustment did not cure it. Link to comment Share on other sites More sharing options...
don80 Posted October 17, 2005 Author Share Posted October 17, 2005 seriously though thats not so good. I thought my 99 Forester had haydraulic lifters but one of the folks here told me it was mechanical. I've never had a problem so I have not looked.I'd start by pulling plug wires to see if I could isolate it to one cylinder if a valve lifter adjustment did not cure it. Ok i tried The spark plug pull method at the ignition coil and isolated it down to a particular cylinder. Pull wire sounds goes away. Wow does the fire ever fly around the coil when i did this. Glad i turned it off between test. I have read this still could be a lifter ajustment problem. I noticed this problem smoothes out and goes away above 4Krpm but returns below 3krpm. HUMMM Link to comment Share on other sites More sharing options...
nipper Posted October 17, 2005 Share Posted October 17, 2005 wheres the fun in that ...your supposed to pull the wires and go OWOWOWOWO ...its an audible spark test hehhee glad you at least found the location nipper Link to comment Share on other sites More sharing options...
Gnuman Posted October 17, 2005 Share Posted October 17, 2005 seriously though thats not so good. I thought my 99 Forester had haydraulic lifters but one of the folks here told me it was mechanical. I've never had a problem so I have not looked.I'd start by pulling plug wires to see if I could isolate it to one cylinder if a valve lifter adjustment did not cure it. Cookie, I have the FSM in front of me. Your 99 EJ25 has solid lifters (well, shims). Only the 96, IIRC, had the Hydraulic Lash Adjusters. Link to comment Share on other sites More sharing options...
Al_SemC Posted October 17, 2005 Share Posted October 17, 2005 Cookie, I have the FSM in front of me. Your 99 EJ25 has solid lifters (well, shims). Only the 96, IIRC, had the Hydraulic Lash Adjusters. I second that. In '97, they changed the EJ25 from hydraulic to solid, the Phase II DOHC motor. The Legacy got that through MY00 until they switched to the SOHC Phase III motor that has screw-type adjusters in the rockers. Incidentally, don80, have you used the Mechanic's Stethescope, aka the Really Big Screwdriver to locate the general location of the sound? My motor (which has 30k on the bottom end and thus doesn't, rather shouldn't have rodknock) makes that same type of noise -- a clicking over 2500 that isn't there while the engine is cool-ish. I've tracked the noise down to three really loud injectors. Maybe you have the same problem? If that's it, try running some cleaner through it. I hear Seafoam works well in the gas, though I've never tried it. I'm partial to Castle Fireball (may not be available except in Rochester and Buffalo, NY) and Chevron Techron. Link to comment Share on other sites More sharing options...
nipper Posted October 17, 2005 Share Posted October 17, 2005 if the noise goes away with the remval of the plug, its rod knock. Lifter noise will not go away with the spark removed. nipper Link to comment Share on other sites More sharing options...
don80 Posted October 17, 2005 Author Share Posted October 17, 2005 I wonder if the fact that the knock goes away above 4krpm means anything? I changed the plugs to bosch 4 plat. about 2 mon. before this noise happened. Could crappy plugs be causing this in some weird way. i really like this car and I intend to keep it for a few 100k unless I drop a few engine parts along the road somewhere :-( Link to comment Share on other sites More sharing options...
cookie Posted October 17, 2005 Share Posted October 17, 2005 I almost never hear or a wristpin noise anymore. I would put a guage on it and check the oil pressure. Next step is to analyse the oil to see if it has bearing material in it. If it does it needs to come apart before it does it all by itself. If it were my car I wouldn't drive it until I had identified the noise. Any knock on the cam or lifters should not stop if you pull a plug, but removing the valve cover to inspect would be a good thing to do. A damaged piston will usually make the engine run poorly. Link to comment Share on other sites More sharing options...
don80 Posted October 18, 2005 Author Share Posted October 18, 2005 I second that. In '97, they changed the EJ25 from hydraulic to solid, the Phase II DOHC motor. The Legacy got that through MY00 until they switched to the SOHC Phase III motor that has screw-type adjusters in the rockers. Incidentally, don80, have you used the Mechanic's Stethescope, aka the Really Big Screwdriver to locate the general location of the sound? My motor (which has 30k on the bottom end and thus doesn't, rather shouldn't have rodknock) makes that same type of noise -- a clicking over 2500 that isn't there while the engine is cool-ish. I've tracked the noise down to three really loud injectors. Maybe you have the same problem? If that's it, try running some cleaner through it. I hear Seafoam works well in the gas, though I've never tried it. I'm partial to Castle Fireball (may not be available except in Rochester and Buffalo, NY) and Chevron Techron. I will do the old screw driver test and pin noise down futher. Right now drivers side front piston most likely area. where can i order a decent Manual for 99 forester? Thanks Link to comment Share on other sites More sharing options...
cookie Posted October 18, 2005 Share Posted October 18, 2005 that should tell you if the injector was making noise. Anybody done this on a Subie? When I was looking for a noise on my ex mercedes I did that and threw a code. I had to clear the code after working on the car. Pulling the plug and inspecting it to see if it looks normal would also be good. I have seen one with a cracked insulator that caused noisy preignition. Link to comment Share on other sites More sharing options...
Setright Posted October 18, 2005 Share Posted October 18, 2005 I like that suggestion Cookie! Link to comment Share on other sites More sharing options...
Al_SemC Posted October 18, 2005 Share Posted October 18, 2005 I'm pretty sure that would be interpreted as a misfire on the cylinder you diabled the injector for. That would represent a code you'd have to clear. Take it to AutoZone when you're done and have them do it for free? Link to comment Share on other sites More sharing options...
johnphils Posted October 20, 2005 Share Posted October 20, 2005 Hi, They had some piston problems on those and have come up with updated pistons. My 99 forester with 2.5 (115000 miles)is making this nagging engine knock once i get up around 3KRPM. it's not there cold but gets there when it warms up and remains even in idle. Once cooled down with engine off it goes away once again until warmed up and driving. I guess it could be a plugged valve lifter if this model has them . Sounds more knocky then tappy like i would expect a lifter. Link to comment Share on other sites More sharing options...
Al_SemC Posted October 21, 2005 Share Posted October 21, 2005 Hi,They had some piston problems on those and have come up with updated pistons. Well, they're not "updated" pistons; they're "countermeasure" pistons. That is, they're specially designed pistons with longer skirts with less propensity to slap. They're specifically for owners under warranty that continually complain about the slap and waste techs' time by bringing the car in for diagnostics. I myself am not big on the countermeasure pistons for two reasons: first, they're heavier and thus reduce the engine's ability to make power, reduce free-revving capability and increase bearing load and second, the "slap" has been proven to have no ill effects whatsoever on the long term. They're basically SOA telling you to STFU. Link to comment Share on other sites More sharing options...
mrk610 Posted October 21, 2005 Share Posted October 21, 2005 I have had the countermeasure pistons installed in my car . I have a 02 outback that developed the slap at 6k miles . BY 48k miles the knock was there all the time . I saw the my engine apart and the new pistons . I could not tell the difference between the old and new pistons . I did have some wear on the pistons by the wrist pins, but the cylinder walls looked great . I now have 59k miles on her and I still have some noise but alot quieter and it goes away in about 3mins or when temp is normal . I read somewere that a loose spark plug or loose plug wire connector could make a knocking sound . Have you checked all the plugs and wires to make sure all is tight . Link to comment Share on other sites More sharing options...
cookie Posted October 21, 2005 Share Posted October 21, 2005 A human that has actually seen the counter measure pistons! That seems to be as rare as a yeti sighting, but nowhere near as common as alien abductions. Link to comment Share on other sites More sharing options...
blitz Posted October 21, 2005 Share Posted October 21, 2005 I have had the countermeasure pistons installed in my car.Were all four replaced, or only two? If two, which ones? Link to comment Share on other sites More sharing options...
johnceggleston Posted October 21, 2005 Share Posted October 21, 2005 i just bought a 97 obw with an engine noise. louder at first start up less after warm up.drove it home 300 miles and it runs great. i was told the car needed an engine, and it was priced accordingly. the dealers mechanic diagnose it as a "wrist pin". said it went away when the plugs were pulled on that side. question: 1. how to tell the difference between bad "wrist pin" and piston slap? 2. will piston slap damage the engine? (apparently not) 3. timing belt is due soon, is it foolish to spend the money if engine is bad? 4. is it better to spend the money on 95 2.2l (167k mi) and move it to the 97 obw? the 95 trans went bad just after new timing belt, water pump, front seals and valve cover gaskets. any help would be great. john Link to comment Share on other sites More sharing options...
mrk610 Posted October 23, 2005 Share Posted October 23, 2005 I had the #2and#4 pistons replaced. The DSR for SOA in my area stated that there was a problem with the machining process with those cylinders. I also talked at some length with the Subaru tech at my dealership ,and he stated that the new pistons had a thicker coating of moly on them. That is supposed to compansate for the bigger bore clearance on the #2,4 cylinders. Also just got 4 new GY Triple tread tires installed ,great tire. MikeK Link to comment Share on other sites More sharing options...
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