Honda ridgeline oxygen sensor bank 2 sensor 1;is it upstream or downstream

Bank one is front side of cat. It should also tell u if it's cat 1 or cat 2. Depending on make an modle an yr. Catalyst 1 bank 2 is left cat back sensor. Catalyst 2 bank 2 is right cat back sensor. U do not have to replace upstream also. My o2 sensor Catalyst 2 bank 2 went bad. Had engine code for burning rich bank 2. Replaced tha down stream sensor an fixed problem runs better an better gas. This was in 97 gmc suburban. Idk what vehicle ur askin about. An I'm not to familiar with much about cars jus trucks an suvs.

In the OBD codes, sensor 1 failures are upstream and sensor 2 failures are downstream. If you have more than 2, then Bank 1 is for the ODD cylinders and Bank 2 is for the EVEN cylinders.

Hi Jesus, Im AL the owner of Big As Auto Repair.

If you have a 4 cylinder engine then you will only have two 02 sensors 1/1 is upstream and 1/2 is downstream. Upstream is the one closet to the engine and downstream is the one farther away from the engine.

If you have a six OR eight cylinder engine you will have four 02 Sensors. 1/1 means Bank One Sensor One. 1/1 and Bank one means right bank and right bank means the side with the number 1 spark plug. SO, 1/1 means, "Right Bank" Upstream 02 sensor. 1/2 means, "Right Bank" Downstream 02 sensor.

2/1 means, "Left Bank" Upstream 02 sensor and 2/2 means, "Left Bank" Downstream 02 sensor. Hope this helps and please visit my auto-repair-website at: http://www.bigasautorepair.com/

The upstream on bank 2, which is the opposite of bank 1. Bank 1 is the side with the number 1 cylinder. Downstream oxygen sensors (after the cat converter) are always sensor 2, as in Bank 2, sensor 2.

Here is the low-down on oxygen sensors, and their location designations explained:

Oxygen sensors are screwed into the exhaust system at various points. Some people say that there are 4 oxygen sensors, but technically, that is not correct. Only the front 2 are considered oxygen sensors.

These oxygen sensors are screwed into the exhaust pipe or directly into the exhaust manifold, one on each bank. Because they are in front of the catalytic converter, this is often referred to as 'upstream'.

The other 2 are actually called catalyst monitors. They are oxygen sensors, but they serve a different purpose. They monitor the activities of the catalytic converters, thus the name, catalyst monitors. They are screwed into the exhaust one on each bank, after, or downstream, of the catalytic converters.

On a 4 cyl engine, there are only a total of two such sensors, the one in front of the catalytic converter is the O2 sensor, the one behind the cat is the catalyst monitor.

The location names for them are as follows:

• On a 4 cyl, the front / upstream is called "bank 1 sensor 1" and the rear / downstream sensor is called "bank 1, sensor 2."
  
  
• On a V6 or V8 engine:
  
  
  • the passenger side bank on a forward facing engine, or the bank closest to the firewall on a transverse mounted engine, is bank number 1, so the forward / upstream sensor on that bank would be "bank 1, sensor 1."
    
    
  • The driver's side bank (forward facing mount engine), or front bank (transverse engine) would be bank number 2, thus the forward / upstream sensor on that bank would be "bank 2, sensor 1," and the rearmost / downstream sensor on that bank would be "bank 2, sensor 2."

Hi, there are 4 sensors on your truck--two upstream and 2 downstream. The upstream sensors are mounted in the exhaust manifolds and the downstream sensors are mounted just behind the catalytic converters. The upstream and downstream sensors are different. Bank 1 is on the driver's side and bank 2 is on the passenger's side. Please let me know if you have more questions, and thanks for using FixYa.

Fig. Fig. 3: Oxygen sensor-4.3L engines

Fig. Fig. 4: Oxygen sensor-5.0L and 5.7L engines

Fig. Fig. 5: Oxygen sensor-7.4L engines

Oxygen sensors are always numbered like this:
Bank 1 sensor 1
Bank 2 sensor 1
Bank 1 sensor 2
Bank 2 sensor 2

Some manufacturers use a kind of shorthand that reads different, but means the same thing:
Sensor 1/1 or O2s 1/1
Sensor 2/1 or O2s 2/1
Sensor 1/2 or O2s 1/2
Sensor 2/2 or O2s 2/2

Bank 1 is always the side of the engine where cylinder number 1 is located and, of coarse, Bank 2 is the opposite side.
On a 4 cylinder engine, there is only 1 bank and it is always referred to as Bank 1.

Sensor 1 is always the upstream sensor (the one located BEFORE the catalytic converter)
Sensor 2 is always the downstream sensor (the one that is located AFTER the catalytic converter.

Hope helps (remember to rate this).

There is are upstream and downstream O2 sensors. 1 or 2 (upstream) before the catalytic converter which sends signals for closed loop fuel control and OBD II monitoring, and 1 (downstream) after the catalytic converter, which is used to monitor the catalytic converter operation. The PCM monitors the signal from each O2 sensor.

Fig. Heated Oxygen (HO2S) location (sensor 1)-2.4L engine



Fig. Heated Oxygen (HO2S) location (sensor 2)-2.4L engine



Fig. Heated Oxygen (HO2S) location (bank 1, sensor 2) (bank 2, sensor 2)-2.7L engine



Fig. Heated Oxygen (HO2S) location (bank 2, sensor 1)-2.7L engine

I hope help you with this (rated this help). Good luck.

1/1 is upstream sensor on the number 1 cylinder side, 1/2 is the downstream of the number 1 cylinder side, 2/1 is the upstream of the number 2 cylinder side, 2/2 is the downstream of the number 2 cylinder side. Hope this helps.