i have honda element 2005 and it shows engine check sign and one of mech.check with code and find out oxyzen sensor are malfunction and told me requred all 4 sensor to be replace. he also mention that i can drive car. how much it cost to repair.

Even if you change the sensors, if the catalytic converter is old the check engine light may not go out. This is an expensive repair.

You probably only need one sensor and don't do it at dealership it will cost more

You will need to fix it in order to pass the NYS Inspection. You probably only need to replace one, but they're all the same age and the others will fail eventually. It's a good idea to do all 4 if you're keeping it. Will also help overall performance. Probable cost: $450-$900 for all at a dealer. $400-$600 at an independent shop.

It's a 13 year old car of you want to keep it change the sensors or drive it until it stops and just enjoy.