2001 Nissan Pathfinder Check Engine Light "ON"?

Check engine light is on. According to code catalytic converters need to be changed. I have bought the online, exact fit, changed them, turned off light. It came back on saying it needs a tune up. Changed spark plugs, disconnected battery, light is still on. Anyone else had that problem. Some say the EMC computer needs rebooting. If that's the case how much does it cost. Any suggestions would help2001 Nissan Pathfinder Check Engine Light %26quot;ON%26quot;?there may be a reprogram for the computer, its gonna cost about 100 bucks from nissan to have done2001 Nissan Pathfinder Check Engine Light %26quot;ON%26quot;?If the light is still on, it's still showing a code. What's the new code for?2001 Nissan Pathfinder Check Engine Light %26quot;ON%26quot;?you might look at replacing the O2 sensors.2001 Nissan Pathfinder Check Engine Light %26quot;ON%26quot;?go to a nissan dealer they probably fix it

does any ram fit on my computer

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