robbieshonda

I put a header on my 98 civic yesterday my check engine light came on. the car has 2 o2 sensors the header only has one hole.. i spliced to o2 sensor so the wires could reach the hole for it. what can i do to make the check engine light go off.
also what does the o2 sensor do?

integra6650

shows the ecu the aproximate air fuel ratioso it can make adjustments. if the ecu thinks theres 2 then you would probably find them both on the cat like new integras well all obd2 ones at least

robbieshonda

my cars stock exuast had a resinator that was a one peice in the exuast manifold. But when i put on the header and cat back i had to splice the wires to make it reach the o2 hole..im going to fiddle with it dtoday. see what i can come up with

b20guy

The "resonator" you are referring to sounds like your catalytic converter. If you removed that to install a header, and even if you hooked up both your 02 sensors, when the downstream 02 sees the same readings as the upstream 02, the MIL will light. The downstream cat is there to read the "health of the cat". I don't know how immediate this process is, but that's how it should work. So if you put on a header, you eliminated your cat, and your only solution to getting the MIL to turn off is add a cat and have one 02 before it, one 02 after it, or build/buy one of those 02 simulators...