Hello all, My 2000 Corolla has 155K miles and has had a ping issue since about 100K miles. The ping occurs mostly between 55-70. Anyways, I have an oil change coming in a few weeks so I wanted to do a few things. 1. Either use seafoam through the brake booster or water sprayed in the intake. Which is more effective? 2. Do a piston soak. MMO, Seafoam, Berryman's, what to use? Is the procedure pretty easy? Sounds like remove plugs, capful of cleaner in the hole. Let sit overnight, put back together and fire up? 3. Last two tanks before the OCI, run consecutive Techron, SI-1, or Regane treatments. I'm also getting the car looked at soon, and may even try replacing the knock sensor(returning if not the issue :). Just wanted to see if this was a good plan? Thanks in advance!