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Kario

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Everything posted by Kario

  1. Thought I bring this up again as this still does not have a definite answer. I've never been able to diagnose the issue. Each time I tried to reproduce this at dealer the car were somewhat warmed and they never heard it - I don't blame them become if the cars is not just started after seating for a whole day than you really need to know what you are looking for. Than the pandemic hit and I had other more important things to take care of but yesterday I was helping to start a car using cables and I was revving my car engine with and opened hood and there it was with a warmed engine and in neutral the knock was audible at around 2000+ rpm. Here it is: https://photos.app.goo.gl/yJy1oerhmiPjk7Bx8 Much more audible in real life then on recoding but its there if you use the right sound output.
  2. Have you managed to diagnose the issue? I'm not convinced that this is caused by high pressure gas burst. If it was than I expect that this would be common to all gasoline engines.
  3. What mileage does your car have? I've noticed this when air temperature in the mornings got colder. I think it was about 3k miles on the odometer. With this little mileage I think the catalytic converter or the hose can be ruled out...
  4. Ok, so its a short high pressure burst from the valve into an exhaust collector that does not cause a high overall pressure in the exhaust system?
  5. I've had an 2.5 EJ series engine a couple years ago. Also an 3.0 and 3.6 EZ engines. This noise is something that EJ/EZ did not made. It's not that easy to hear it in my recordings. You need a good set of headphones to hear it but if you do hear it that definitely you'll know what I'm taking about. It's not a boxer injector ticking. The high exhaust pressure caused by retarded timing is a theory. If this is the case than it should be more audible in the back of the car. I'm I right?
  6. More information on the topic: 1. I have briefly driven another Outback at the dealer. Looks like the car has the same sound but I think it made less of that noise. Hard to tell with a very short drive. 2. I had a mechanic drive with me and I had a hard time reproducing this due to engine not being completely cold and road/traffic conditions. 3. I made another recording of my car, I think it the best yet: https://photos.app.goo.gl/nwXyhscbgNVCdq9m8 4. I have found a YT vide with a similar noise but definitely worse than my car makes: My current theory is a timing chain tensioner being loose causes the chain to hit the case when the engine is cold. Depending on the particular car this works better or worse and gives less or more of this noise. Maybe someone will be able to confirm or deny this or provide some more info on if this is normal for FB25 and is so to what extend this is normal. Thanks in advance.
  7. A new recording: https://photos.app.goo.gl/5ZH4PtwESxEQ1hi18 I think that its clearly audible at 42-44 seconds. This is a new car. The car has been doing this from day one. Is it possible to have a piston slap on a new car? Should I pursuit guaranty? I think that if this is a piston slap than maybe fixing this might cause more harm than good..
  8. The noise is not dependent on the outside temperature and the fact that the car is in the garage or not. If it's cold outside than it audible later in the drive probably due to a fact that the car holds higher RPM longer when the engine is really cold. The noise is audible as soon as the engine drops RPM after startup but only under very light load. More load - no sound. I've had a legacy EJ25 once with a piston slap once. I think that it was more metallic sound. This is more like a faulty belt tensioner causing belt to hit plastic belt cover under load, but the car does not have a belt. The sound was there from the first km (miles ). If its a piston slap than I think that its strange on a competently new engine. Also FB has a larger stroke / bore ration than EJ so it should be more resistant to piston slap.
  9. I have a 2018 2.5L Outback. When the engine is cold (or the car sit for a while but the engine is still somewhat warmed) under very lite acceleration I can hear a knock coming from the engine. Here is a link to a video: https://photos.app.goo.gl/FBu8Yts9uwVzqu828 Best to listen with headphones. It looks like the car is not moving but I have recorded this on a hill and the car is moving slowly under lite throttle. Some info: - You can hear this only under lite throttle. - It gets quieter or is completely gone after a few moments. - The engine needs to be cold, or sit for a while. Does not have to be 100% cold. With freezing temperatures it actually better reproducible when the engine it somewhat a bit warm but the car was sitting for a hour or so. - The throttle input needs to be constant to best reproduce this. The car has about 4k miles but it did this from day one. I'm not going to a dealer with this yet because I talked to them, they have never heard of this problem and will probably take the car for multiple days and will have to disassembly stuff piece by piece until they maybe find something. Better to start with a solid theory. First question: is this normal? Second question: if this is not normal than what might cause this?
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