I've had TONS of problems with engine knocking when accelerating and have taken it to the dealership 3-4 times already and am way past pissed at this point. They've cleaned carbon buildup, cleaned fuel injectors, and recommended using a higher octane fuel. All have worked for a few months, but then the same thing just happens again! Oil and filter change every 3000 miles, replaced air filter and fuel filters regularly and even tried the fuel injector cleaners that you pick up at the store. I just saw on a post where there was a TSB issued because of spark knock on acceleration for Ford vehicles equipped with a 3.8L engine, which I've never been able to find before. I was wondering if anyone else has had this problem and followed the instructions in the TSB and what were the results???? Any info would be GREATLY appreciated!!!!!!!!!!!!!!!!!!!!!!!!!!!