The check engine light has come on and I manually checked the codes. I have 0303, 0304, 0503, 0701, 0806. The information I have researched so far tells me the following are reported problems - Front left O2 sensor, Knock sensor, Front right O2 Sensor, Multiple cylinder misfire and Evaporative emission canister purge control solenoid valve. Is there something common that I should look at first? The car has close to 250k miles on it.

 

Look at the "check items" and see if you see anything in common. Honestly, I'd start at the KS and front left O2 sensor then go from there.

BTW, the images are in code order as you listed.

 

Thanks ChrisMan287. I will start there.

 

From what I see, it seems that fuel is common in all cases...

 

seems the misfires could cause the rest of the codes to me. maybe find out why it's missfiring. whether that be bad fuel or a ignition (spark) problem. wouldn't think a bad o2 would cause missfires in all cylinders and it's not like it's just one cylinder it's all 6. the fuel delivery problems may also be a problem, thats's definately a common cause. I would check my fuel pressure and spark before I bought anything.