Sunbird Engine Clean

What is a good product that I could use in my engine to burn all the crap out of it? The car is running a little rough at 216000kms. I figured I would try something to clean the engine out....

Also, Acceleration through 2nd gear is rather choppy. I replaced the spark plug wires as the one wire had a tear in the rubber. I noticed the rough acceleration more so after they were changed...

Any Idea on those Questions???