2009 Forester engine ping "They all do that"
Hello everyone. I have a 2009 Forester that pings under light to moderate acceleration when pulling away from a stop sign or driving between 20 to 40 MPH and maintaing speed on slight hills and is audible with the windows either open or closed. My Forester has only 8500 miles on it and I have always used "name brand" gasoline from various stations. I took it to the dealer today and was told that this is a common issue with this type of engine because of the cylinder layout/orientation. I personally feel that this is a bunch of bull___. I feel that with modern day electrical advanced timing and knock sensors this should be a thing of the past and that "ping" or "knock" is really detonation and not a good thing to have happening inside my engine. Anybody have any comments? Thanks for any help.
This discussion has been closed.
Pinging should not be happening in a modern engine, if you are using suitable fuel.
Try running the vehicle on Premium Unleaded from a single source for a few tanks. If you can source Shell's Premium Unleaded (it might be branded as Optimax or V-Power or some other name but typically 95-98 RON with detergent additives). This has the benefit of improving fuel economy and reducing coking in many engines.
When I first ran a Subaru, I had various problems with the engine. Subaru's senior engine tech in Australia visited and replaced the ECU (which was remapped a little) but said that the single biggest cause of engine problems was poor fueling. He recommended Shell Optimax and I was surprised at improvement in performance, removal of bad engine issues and most of all by 10-15% fuel economy improvement.
Subaru in Australia also recommend adding a top engine cleaner to two tanks of fuel every 10,000km or 20,000km. This tends to reduce coking which may be contributing to your coking and extends service life of the engine.
Agreed, but the sound may not be pinging. The exhaust manifold rap on some Subaru fours might confuse a new owner. My four had it but my 3.0R six does not.
Graham's advice is good to try. The higher octane V-Power Shell should not ping at all, and the higher detergent level just might clean out some deposits that have accumulated. After a couple of tanks and then returning to the 87 octane, if the problem persists I would pursue the numb knock sensor thought.
Just out of curiosity, what area do you live in, and do they use 10% ethanol? Does this happen all the time or only when it is hot and you have the extra load of the AC system? Has anyone made sure your cooling system is full with no air pockets?
Overall I am very satisfied with the cars
The engine is supposed to run on 87 octane without pinging, period. You have far to few miles for "coking", but even pinging from that would be suppressed by the knock sensor and ECU. Pinging is not a common issue with the boxer engine, as my 2008 has no trace of it, nor have I ever heard of it in two years of heavy participation in the subaruforester.org forum.
If the knock sensor was faulty, I would expect to see a trouble code. I would try a couple of tanks of high octane, just to see if it had any effect. If that stops the pinging, then something is wrong with the sensor or ECU.