Getting a "Catlyst Efficiency Bank One Code" on my car - perhaps need to change the oxygen sensors - tech says the engine needs to be dropped for this?
Anyone have any experience doing this?

 

What sensor does it specify 1 or 2. Bank 1 sensor 1 can be done with the engine in the car. Alittle tricky but can be done, sensor 2 not so easy you pretty much have to take the motor out of the car.

 

Bank One - they says I need to replace both sensors in bank one - What do you think?

 

My mistake it was a cat code, pre cats on occasion will split into pieces. Any rattles at idle? I would try clearing the code and seeing if it comes back.

 

This is possible would have to see the live data of the sensors.

 

No rattles - cleared the code a few times keeps coming back - dealer says might be cat but has to change sensors first in order to tell

 

It may not rattle, I would have them unbolt the precats (motor has to be out to do this) they should be able to see if they are starting to come apart. If you are doing this i would suggest changing the sensors on bank 2 as well, so you don't have to go through this again.