The EVAP code could be related to the knock sensor code. I am assuming that the knock sensor code you are getting is the p0325 code. The sensor is essentially a microphone set to a certain frequency range of tolerable noise from your engine. It can be set off by harsh acceleration, engine ping, or even a rock kicked up from the road bouncing of the outer casing of the engine. Essentially the knock sensor is to be ignored as you will have other codes that accompany it if you are truly having a problem.

 

thanks ,no problems cept that ses light is on then when i unconnected the battery the other day(cleaning the posts) it went off then after a few days it came back on:lame: its annoying:crazy:

 

the evap system could have a problem, but I couldn't tell you what it is. A problem in the EVAP would cause poorer than normal fuel economy, though my 98 gets brutal economy anyways and it is showing no codes...

 

the knock sensor code is just a stored code. most times, if nots just a noise, as noted above, then you can take the sensor off and clean it, then reinstall it.