Shaynepolevault

Where is the first o2 sensor located? The one from the cel codes guide labeled o2a. I have a 1999 si want to know because i got a check engine light, and through a code 1 need to replace the o2 sensor.

Shaynepolevault

how many oxygen sensors are on a 1999 civic si? Are there only 2 one before the cat and one after?

solattack77

i would think two since its obd-2

EJ8_Enthusiast

yeah, 2. the back one monitors how well your cat is cleaning the exhaust.

the first one should have an adapter, the second just has wires that run up into the floorboard.

ahobbs

one under near the half shaft, then one the cat

Shaynepolevault

When I do the cel check if there is 2 codes how long is the pause between the 2 codes? Because before i thought i was getting 11 now I think im getting 10 and 1. And does it matter the order. or am I suppose to get 1 first and then 10? Becasue right now im getting a long flash so 10 then a long pause the a quick flash so 1 Im guessing?

B18C5-EH2

You should really hook up an OBD2 scan tool and read codes from that.

The two wire jumper method used for OBD1 cars isn't always specific enough, and OBD2 cars throw codes that OBD1 cars don't so how will you use an OBD1 method to properly check those codes?

Although I hate Auto Zone they do free OBD2 diagnostic hook-ups with a scan tool - stop by one and have it scanned for FREE.

Just don't be surprised if they try to sell you their crappy parts to "fix" your check engine codes.

Shaynepolevault

So does anybody know how accurate the ob2 jumper plug method is for 1999 si if the code are right or not.

scbmx87

Not very, take it to autozone and have them scan it...its free.