Okay, I just changed the spark plugs to Bosch plat 2's and wires. The day before that, I had the oil changed. Now, occasionally when the car is running, the engine sounds like it is squeeking. It gets faster as the rpms go up. Sometimes it's there, sometimes it's not. Any ideas? When I took the old plugs out, there was some dust around the plug holes, that I was careful not to get any in the block. Hopefully, that has nothing to do with it. If it did, could I just drain the oil and refill again or something or am I screwed?