I feel like I am asking a dumb question but I have to. Which sides are bank 1 and bank 2 left or right. The reason I ask is because my check engine light is coming on and my OBD 2 reader is telling me the catalytic converter is operating below efficiency bank 2. I pulled out all four o2 sensors and looked inside with my bore scope. On the right side the up stream sensor looked kind of black along with the down stream sensor. The honey comb looked intact up stream and down stream. The left side upstream sensor looked quite grey almost white the down stream sensor looked pretty much black. The honey comb looked good upstream but the down stream side has a large gash across it with a melted blob. I plan to replace the cats with Magnaflow 59975. I believe the previece owner ran the car with a bad coil which has been replaced. So I am wondering if the left side is bank 2 which would explain the over fueled burnt out cat. I am riding the fence on replacing the remaining 5 coils yes 5 coils dam removal and install intake manifold. Any insight any one has would be greatly appreciated.

 

Here you are

 

At 136,000 not sure how far you wanted to go but reading some of your other posts you have already done some nice projects so my guess is you want to keep the car. I replaced all the coils and plugs and when doing so, was suggested to do a couple of other things while I have it apart. Changed the gaskets and the o-rings and some L tubes(can't think of the name) but listed often on here. And make sure if never changed, when you have to take some of the hoses off to remove things, one in particular that goes three way with the coolant at the top could break on you so be ready. I used a part that splits 3 way (auto zone has them also) I got at home depot and has been working fine ever since. Good luck.

 

Thanks you all Richard