I have a custom manifold, t3, and i have a d16y7 engine with two o2 sensors. What do i do and where do i at ;east put the one.

 

one before the cat, and one after the cat.. so in the downpipe, and the other one after the cat... Or if you are going to run no cat, on OBD2 you will get a CEL some type of catalyst efficency code, because they will read the same, so you would need a o2 simulator..

diablo motorsports has one.. dont have the link right at the momment

Jeff

 

what is a CEL?

 

Check Engine light

 

yeah, if you don't run a cat it's a pain in the ***. trust me.

but when jdmfan.com is up they have a "how to build your own o2 sensor simulator" which consists of about $21.50 CDN in radio shack parts. (i priced them out myself.) be sure you go to a large radioshack because the ones in small hick *** redneck towns like mine will have to order half the stuff required.

i'll scan the page i printed off (don't mind the scribbling and the dirt) and post it here in a minute since jdmfan.com is down due to financial troubles.

 

 

great info!

 

good info. i have cel anyway because of baro sensor. i get the o2 efficency too since my o2 sensors are so far seperated (one in the std manifold o2 bung and one in cat outlet after the downpipe). i guess the exhaust cools more than it expects. it doesn't seem to affect my fueling, by a/f gauge reads the same as it always does and hits rich when i get over 45-50% throttle like stock. does anyone know if it is supposed to affect anything like fuel or timing? my car still pulls real strong.

 

Good question!

I had this same doubt while building my downpipe, I put my o2 bung near the same place my greddy n/a header had the fitting, which is about 10 inches before the cat........BTW, I am running OBD I......seems to do just fine......

 

i took my second o2 out and pluged the hole then just safety wired the sensor around my exhaust so it stays warm and my cel hasnt came on. ive had it like this for about 2 months now. btw i drive a 98 civic