tominredbank Posted January 8, 2006 Share Posted January 8, 2006 Hi all, First post on this board, hope someone can help. I have a 2004 Forrester with 29,000 miles on it purchased new. This winter I noticed a prolonged valve tap( at least that`s what it sounds like) until the engine gets very warm. 15 to 20 minutes driving. It will tap under load until it warms up and drives me crazy. The thing is it didn`t do it last winter at all. The dealers and SOA tell me it`s normal but I just don`t buy it. Are these valves adjustable? I realize it`s a solid lifter cam but there must be some adjustment. The dealers I called say no. SOA told me a story about the pistons and writ pins being lightweight and a 20 minute tap is normal. Can anyone help me load up with some information before I go back o dealer? Thanks, Tom H Quote Link to comment Share on other sites More sharing options...
ShawnW Posted January 8, 2006 Share Posted January 8, 2006 There is a valve adjustment that can be done and its not terrible to do in the car. I am surprised they arent trying to sell you something when you suggest it. Quote Link to comment Share on other sites More sharing options...
tominredbank Posted January 8, 2006 Author Share Posted January 8, 2006 There is a valve adjustment that can be done and its not terrible to do in the car. I am surprised they arent trying to sell you something when you suggest it. Can you tell me more? It`s still under warranty. I `m great with cars, I`d rather do it myself if it`s not a bear. Quote Link to comment Share on other sites More sharing options...
ferret Posted January 9, 2006 Share Posted January 9, 2006 Tom, are you sure it's the valves? You may have Subaru's genuine 'piston slap'. That goes away after the engine warms up and other than sounding like a diesel when cold, does the engine no harm. I suspect if the mechanics heard the sound, and it is slap, the answer they gave you, is correct. I don't like it, but that's the nature of quite a few engines these days. Imagine paying over 50K for a Corvette....their forum is full of piston slap issues, and GM gives them the same answer. Quote Link to comment Share on other sites More sharing options...
tominredbank Posted January 9, 2006 Author Share Posted January 9, 2006 Tom, are you sure it's the valves? You may have Subaru's genuine 'piston slap'. That goes away after the engine warms up and other than sounding like a diesel when cold, does the engine no harm. I suspect if the mechanics heard the sound, and it is slap, the answer they gave you, is correct. I don't like it, but that's the nature of quite a few engines these days. Imagine paying over 50K for a Corvette....their forum is full of piston slap issues, and GM gives them the same answer. Pretty certain it is one loan valve. If all of them did it it wouldn`t be so bad. Any way to explain why it didn`t occur last winter? Quote Link to comment Share on other sites More sharing options...
ShawnW Posted January 9, 2006 Share Posted January 9, 2006 The nut on the valve adjuster loosened up over time. It happens. Quote Link to comment Share on other sites More sharing options...
cookie Posted January 9, 2006 Share Posted January 9, 2006 It is pretty likely to be piston slap. It tends to increase with engine wear and last winter the anti-slap coating may have still been on your pistons. My forester does the same thing only it does not last very long as its not that cold here. Adding a heavier oil helped mine quiet down except for the first morning warm up. If you want to you can adjust the valves easily, but if the mechanic did not offer to do that for you its probably not the valves. If you can make a customer happy with a valve adjustment you would do it. Piston slap is another major step as it requires replacement of the block and then might only cure it for a while. Subaru does have another piston kit but my dealer does not service them that way. Quote Link to comment Share on other sites More sharing options...
swc7916 Posted January 9, 2006 Share Posted January 9, 2006 I have 4 Subarus and 2 of them do this. These cars have 25k and 29k miles on them. I'm not crazy about it either, but it's the nature of these engines. It's not hurting anything and it goes away in a couple of miles, so I just live with it. Quote Link to comment Share on other sites More sharing options...
Setright Posted January 9, 2006 Share Posted January 9, 2006 Piston slap. And yes, it's because the molybdenum coating is worn off that you can now hear it. BMW's V-10 engined M5 slaps at idle ! So do many Hondas.. Quote Link to comment Share on other sites More sharing options...
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