So I've been hearing alot of talk about Seafoam doing all kinds of good for the car's engine and I'm thinking of running some through the vacuum line. I went out to buy some tonight after having autozone check my service engine light. The codes that came up were 141 and 305. The 305 related to a misfire in cylinder 5. But I'm confused as I JUST changed all my sparkplugs and fuel injector 5 less than a month ago, and my wires and coils about 2-3 months ago.

141 has something to do with the o2 sensor. I replaced the sensor with a brand new a year and half ago but I've heard that GPs have two of them...And I'm not sure which one I had changed as I wasn't working on my own car back then :-/

So as I was saying, my intention was to go in and buy a can of seafoam but the salesguy talked me into buying a bottle of Lucas injector cleaner...and that light is still on...so I've been reading a few tutorials about seafoam and i'm thinking of running it through the vacuum line. Can this damage the car in any way before I do this?