Have a 96 Es with 115k. It's running rough and sounds like it might have an exhaust leak. I'm getting a misfire codes on cylinders 2,4,6 as well as random/multiple and a bank 1, sensor 1 o2 sensor. I'm curious if my deduction that the front manifold is leaking, isn't too outlandish. Anyone confirm or guide me in what should be done? Also is 2,4,6 the front bank?

 

Correct, bank 2 is the one closest to the front of the car. Your deduction seems possible given the combination of symptoms. You can use a piece of hose to listen around the manifold for leaks. Your fix would be to pull the manifold, make sure it is true by placing it on a completely flat surface, if it is warped you may have to have it decked to provide a flat surface. If the manifold is not warped all you will need to do is replace the gasket and reinstall. I experienced a warped exhaust manifold on my old mr2 so it does happen.

 

Misfire could be spark/ignition, or it could be fuel injectors, or both. Your car doesnt have many miles, but the injectors could be bad. Since you have an 02 going off, it may be fuel injectors.

The first thing to do is pull the ignition coil and spark plugs and look at them and their condition. If they look corroded or bad, then replace them. You can get new ignition coils for less than $30 online.

After that, if car is till running rough, you need new fuel injectors. The front bank fuel injectors are easy to change. Everything on the front bank is easy to change, lol.

Go in that order>>> check spark plugs and ignition coils for corrosion and wear. The "wear" on the ignition coils will be bad oxidizing in the boot where it connects to spark plug and maybe even a bit of rust. After, start replacing the fuel injectors as they do go bad. Also, if you replace fuel injector(s) even one, you need to replace ALL the seals on the other fuel injectors on that bank, or youll have fuel leaks. I know because I changed an injector then had fuel leaks on the other old fuel injectors with old crusty seals.