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I recently got the code PO141 after replacing both upstream and downstream O2 sensors, so I have returned those sensors to Amazon and got a better brand on the way.
My question is, from the picture that I have listed, whis is the plug for the upstream O2 sensor and which is the plug for the downstream O2 sensor.
My thoughts are that the connector on the left is the upstream, or bank 1 and the connector on the right is the downstream, or bank 2, since the cabling to get to the plug is longer. The problem is, I have searched hundreds of photos of 1999 d16y7 engine bays and none are mounted like mine, and I just wanted to be sure the right sensor is connected in the correct plug. Also, why are my connectors mounted different than any other 1999 d16y7 that I have seen. They seem so close, but I cannot find another spot to mount the right Plug other than where it is. thanks.
whis plug is for upstream, bank 1 O2 sensor and which plug is for downstream or bank 2 O2 sensor?
The white/red wire on the engine harness side of the plug on top (farthest to the right) is the O2 signal wire for the DOWN STREAM or secondary sensor... which means that the other O2 4-wire plug would be for your UP STREAM or Primary O2 sensor. The primary O2 signal wire color is White... solid White.
Thank you JRCivic1, you the man! any reason why my bracket places the harnesses so close together? all other d16y7 engine bay pics have the downstream plug closer down towards the tranny. Also, sorry to add another question, but could you possibly answer or point me to a post where I can get some info to convert my LX exhaust manifold to EX style? from what I understand, I need am EX header, a high flow catalytic converter, and an O2 extension cable. Is that all that's needed and it all bolts to the stock "cat-bak" existing exhaust? My reason for wanting to do this is because I think that the LX exhaust manifold/catalytic converter all in one is dumb and too costly. I would also like to have a more free flowing exhaust manifold as well. Any help would be appreciated, and once again, I am sorry to post a second un-related issue here, but I am about to order parts and just wanted to be 100% sure I knew what I needed. Thanks, JRCivic1!!
Hmmmm... I cannot answer your second question with 100% accuracy. It is true that you will need an EX type header, a catalytic converter and TWO O2 extension cables... one for each sensor. Keep in mind that the '96-00 EX and Si chassis have the primary O2 sensor plug on the back of the engine harness under the intake manifold and the secondary O2 sensor plug back in the tunnel near the shifter, so this differs dramatically from what you have pictured above. Thus, the O2 extension cables will have to reach these approximate locations so that your primary and secondary O2 sensors can be mounted in the OE locations/areas. Now, as for being able to bolt up to the cat-back... this is NOT possible with the stock one unless you change to the stock EX cat-back (if you have a 2-DR or 4-DR) at the same time. Also, some aftermarket EK cat-back systems are designed as EX style systems with an additional pipe included to make it work on a DX/LX application, so if you have one of these... you may also get lucky and have a bolt-in combination.
Another note: Many "high flow cats" aren't really catalytic converters at all, but in fact resonators. IF the one you purchase is a straight through design (meaning you can see through it clearly from front to back when you hold it up to your eye), a trick like an O2 fouler or electronic trick will be needed to keep the ECU from throwing a "catalyst inefficiency" code.
03-28-2018, 06:20 PM
D16Y7 upstream/downstream O2 sensor plug question
