Ok I just picked up this clean EF9 with a 1st gen JDM B16a, I noticed that it has 2 1 wire o2 sensors at the collector?????? does anyone know why??????

 

thats the way it came. mine has it too

 

Thanx

 

you can bypass the secondary one by wrapping it in foil and tape it up so foil dont come off

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Go n 4 10s &raquo;</TD></TR><TR><TD CLASS="quote">Ok I just picked up this clean EF9 with a 1st gen JDM B16a, I noticed that it has 2 1 wire o2 sensors at the collector?????? does anyone know why??????</TD></TR></TABLE>

You picked up an EF9.? are you sure? But yeah thats normal to have the 2 o2 sensors on the obd0 b16a..Its a pain in the *** when you want to get an aftermarket header though..I chipped my ecu and deleted the o2 sensors all toghther..

 

Yup its a 90 civic Hatchback, and Thanx for all the help I think I will just leave it alone

 

dude, all pre-obd b16a's have two UNheated (single wire) oxygen sensors on the header, high near the block.

only in obd-1 and up cars did they start putting 4 wire heated o2s down low.

chances are your car is running the original pre obd ecu: pr3 or pw0

hence it MUST have 2 o2's to run correctly. unless you chip the ecu to run without it, or do an obd-1 conversion and run a p28

dont listen to poeple telling you to use tin foil? wtf it will run rich and bog when it shouldnt at WOT if you only run one. anyone running only a single on an upchipped ecu your robbing horsepower from yourself.

just run the extra wire to the ecu and call it a day, its easy. if the swaps already done and your dont notice bogging or running rich then the person probably did the swap correctly.

search next time!