So I recently bought a 97 limited with the knock sensors giving a CEL, didn't seem like a big deal because I was gonna get them replaced quickly. Well two weeks into ownership my HG pops so I get all of that straightened out and the mechanic was saying that the CEL could of been caused by the HG going out and it picking it up, kind of like an early warning. Well the CEL is still there and my gas mileage seems a little lower than it should, sitting at around 15 mpg. Now should I go ahead and get them replaced asap, its both of them which seems kinda weird. The mechanic said he didn't want to replace them both if they weren't truly bad, the sensors he priced were 250 a piece. I have found some on rock auto for way cheaper and may buy 2 and eat the labor on them 
Thanks for the help people, if any of you know me from my other ventures, I come in peace :biggrin2:
Thanks for the help people, if any of you know me from my other ventures, I come in peace :biggrin2: