Installed headers on 93k5. Stock manifold had an O2 sensor on Drivers side. Must that be reinstalled so it runs right or can I get away without it. I know in newer vehicles the oxygen sensor can really fowl up the way it runs

Bank One and Bank Two refer to the sides of the V shape layout of the engine. Stand with the engine belts and pulleys nearest to you and the transmission (Gearbox) furthest away from you. Bank One is the Left side of the engine as you are looking at it, Bank Two is the right side. You need to look at the exhaust manifold and exhaust pipes on the RIGHT side of the engine.
There are Two o2 sensors in each exhaust, (4 in total on a V6 engine), One before the Catalytic Converter and one after it. They are labelled as Sensor One, (Before the Catalytic Converter), and Sensor Two, (After the Catalytic Converter).
'Sensor One' o2 sensors are sometimes mounted directly into the exhaust manifold nearest the engine or possibly in the Catalytic Converter itself.
'Sensor Two' o2 sensors are further down the exhaust ,often in the bend as it turns to go under the vehicle.

It should be easy to find. It is between the exhaust manifold and the converter.

you may can try this drain radiator fill with water only disconnect battery if light stays off then you intake manifold gasket failure , antifreeze will cause o2 sensor to go and eventually clog cat converter

You should have 2 o2 sensors.... Your 1st should be bolted onto your exhaust manifold (headers)on the side. You should be able to see it easily when you open your hood. The secondary O2 sensor should be bolted onto your cat-convertor.. Find yourself the right wrench and unscrew it...
Easy process...estimated time should take 3 min....

bank 1 is the drivers side bank, so b1s1 would be the drivers side closest to the engine. if the truck is equipped with several 02 sensors then bank 2 or b2s1 would be passenger side closest to the engine. those are called upstream o2 sensors and the others downstream b1s2 and b1s2 b= bank 1= drivers side s=sensor 2=downstream. hope this helps.

If the truck is fuel injected and probably is the aftermarket headers are sending a signal to the computer and feeding more fuel to the engine fuel is controlled by the intake and exhaust.as for the o2 sensors you will be fine without them they only turn on your engine light when it
has been covered in carbon monoxide to the exhaust.

You need to check two things.

First, there is a heat shield on top of the front of the motor where the o2 sensor you already replaced is. It's got (4) 12mm bolts. Remove it and check the exhaust manifold (big thing you put the o2 sensor into) for cracks. If there are any cracks, you'll get o2 sensor codes. Replace the manifold.

Second, if the manifold is fine start the car and listen to the exhaust pipe under the engine for leaks. Or if you already know the exhaust is loud... that's gonna do it too. A leaking exhaust pipe on an Accent will set secondary o2 sensor codes.

SHOULD you try to change it yourself, you will need a 7/8" wrench, and a new o2 sensor, or flex pipe, or manifold depending on what's broke. Do NOT touch the tip of the new or old o2 sensor to ANYTHING when you take it out or install it or it will be ruined permanently. Run the car until it's at it's normal operating temperature. Raise the vehicle, and take the o2 sensor out of the car (see below to understand which one) using the 7/8" wrench or if you got fancy and bought an 02 sensor tool... use it.

Replace whatever parts are bad (manifold or pipe) or just replace the sensor you need. Then restart the car and take it to a parts store and have them clear the code. The code (and check engine light) won't return right away, it usually takes a few days. If you did everything right you should be good. If not, it's not a terribly expensive job to have done and by now you should be able to explain to them what's wrong based on what you found when you looked at the car. Just tell them everything you checked and what you saw.

Education: I'm not sure where that half baked answer about o2 sensor 1 being near cylinder one came from but here's the real deal.

Sensor 1 is always BEFORE the catalytic converter
Sensor 2 is always AFTER the catalytic converter

Bank 1 and Bank 2 refer to which SIDE of the exhaust on 6 and 8 cylinder engines. Bank 1 is usually left side, Bank 2 is usually right side.

So... O2 sensor B1S1 refers to the O2 sensor BEFORE the converter on the LEFT side of the motor.

YOU HAVE 4 O2 SENSORS. YOU HAVE 2 PASSENGER SIDE.ONE O2 SENSOR ON EXHAUST MANIFOLD THE OTHER ONE AFTER THE CATALYTIC CONVERTER.YOU HAVE 2 ON DRIVERS SIDE.ONE O2 SENSOR ON EXHAUST MANIFOLD.THE OTHER O2 SENSOR AFTER THE CATALYTIC CONVERTER.

the o2 sensor is on the exaust manifold on the left side of the vehicle where the flange of the manifold meets the resonator right befor the catalayic convertor

hi im wesall o2 sensors are located in the exaust system yours has one before the converter one after if it has duall exaust before the cat on drivers side will be upstream sensor bank 1 after cat right side will be bank 2 sensor 2
thanks wes
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