2012 Forester Ford E450 Spark Knock
Several months ago, I made a post describing a problem that I had with spark knock (pre-ignition) on my MH with 30,000 mikes. I used several major brands of fuel, changed the air filter, disconnected the battery in hopes of resetting the computer, all to no avail.
Then I read about cleaning the Mass Air Flow sensor in the air filter canister, using the special spray cleaner for that purpose. It worked!! No more spark knock.
It's quite simple to do and wanted to share