obdo b16a in my 89 crx si

[so_lo_crx89]

ok so im new on here and and i was wondering if someone could help me out on wiring up my o2 sensors right now i have the wires spliced together as if i was running 1 o2 sensor but i know thats not right i want to fix this problem. i have a pr3 ecu im pretty sure. please help me

 

[so_lo_crx89]

can someone please help

 

[monotech]

Secondary o2 sensor pinout is C8 Run a wire from ecu to secondary o2 sensor.

https://hondaswap.com/parts-sale-trade-wanted/conversion-harnesses-4-sale-143438/http://hondacamp.com/index.php/topic,116.0.html

 

[so_lo_crx89]

thank you....ok so here'sanother question i have a 4-2-1 header. my o2 sensor is in the collector on the downpipe. where should i get the second o2 bung put in.

 

[Bkkfarang]

close

 

[Bkkfarang]

sorry close to the area just behind the cat or where the cat should be

 

[BrokenRex]

the two sensors belong in the first merge of the primaries before they run down into the collector. one goes in each of the secondaries on the rear of the exhaust manifold (before it goes down into the "b-pipe" that connects the manifold to the cat). i had a later manifold drilled and welded two sensor bungs into it, then plugged the old sensor bung with a bolt. the ecu on obd0 b16 motors is a finicky bitch if you try to wire up the o2's backwards. i imagine that having one that far downstream and the other in the right place is going to piss her off. but let us know how it goes if you do go that route.

 

[so_lo_crx89]

so i should put them in the two pipe after where the four pipes come together?

 

[BrokenRex]

yeah, if you can. this is the header on my OBD0 b16, it's not the factory piece, but it's got the same layout. you can see one of them, and the other one you can see the wire going to it. this is how the ECU wants them to be. you can try it out however you want, but dont be surprised if you're disappointed with the results.

 

[so_lo_crx89]

hey thanks that helps alot and im gonna get working on it. oh by the way i have the same header except mine is not a two piece my downpipe is made on to it. but its a 5zigen

 

[Bkkfarang]

honesly i went to one o2 sensor when i did mine thats was in the header collector , and had no issues with my ecu , but mine was rechipped and fully tunned

 

[BrokenRex]

yeah, mine is a 5zigen as well. mine had a shorter length than the USDM ones though. i had to add an inch and a quarter and clock the flange differently. luckily i met a guy with a tig welder just before i bought it.

bkk, most of the "chipped" ecus are programed to run on a single added wire for vtec. they forgo knock sensor, vtec pressure switch, and secondary O2. that's always an option for anyone who wants to avoid a headache. but on the 91octane feline piss they sell around here, i'd take the headache anyday to have a knock sensor in there retarding timing when things go bad.