getting some ideas...The engin light comes on runs great had it read replaced gas cap took out the mass air flow and cleand it, take the neg. battery end off for 30 min. put back on. light off for 100 miles and comes back on....any ideas.

Have it scanned figure out what the code is. You can't just throw parts at it.

took to the zone they said it was a 420 code

your cars been smoking too much pot...

P0420 Catalyst System Efficiency Below Threshold (Bank 1)

http://www.obd-codes.com/p0420

Switch the two O2 sensors see if the code moves to bank 2 if so its just an O2 sensor.
I had a P0430 code for a while and I had to get a new cat, but it solved the problem. If it comes to that it will be covered under warranty as long as your under 80,000 miles

had it read and it said
P0420 Catalyst System Efficiency Below Threshold
also said that the 02 sensors were ok

took to the dealer turns out the cat. is bad, dealer cost, thanks for all the help