Cat converter is bad. Try changing out the O2 sensor first. If that doesn't work, you may have to change out your catalytic converter. Try rock auto for the cat converter. Usually the cheapest prices around unless you can score one on Ebay.
http://www.obd-codes.com/p0420 --- check this out. You might find the info helpful
Nissan Frontier
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Maintenance & Repair
Heater will not blow warm air unless the truck is moving forward. I have to turn heater fan off if I stop for stop sign or stop light. If I don't turn off fan then cold air will begin blowing out in ...
2006 Nissan Frontier
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Maintenance & Repair
Switch on the front left side that's depressed when the hood closes. Is this part of the factory alarm system? The alarm goes off randomly in hot weaather.
2001 Nissan Frontier 4 Dr SC Supercharged 4WD Crew Cab SB
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Maintenance & Repair
timing belt is starting to go, am getting the parts i need to replace it, ( the kit at rock auto ), i was told to make sure i get the tvti with it.
2006 Nissan Frontier XE 4dr King Cab SB with automatic
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Maintenance & Repair
It runs fine until it gets to a light then it misfires and it dies and won't start again has had maintenance such as changed spark plugs / wires / pressure check on valves/ some sensors changed / ...
2000 Nissan Frontier 2 Dr XE Desert Runner Extended Cab SB
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Maintenance & Repair
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