Will aftermarket headers and high-flow converter cause the cel to pop up?

[yairsaenz83]

This is my o2 sensor nightmare. A week ago my check engine light came up. Two scans brought a p0137 (sensor 2, after cat, having low voltage). I replaced the bad sensor with a Bosch sensor. The cel came up again a day later. I returned it and bought a universal denso sensor. I don't want to put in the Denso sensor since I am afraid the cat might be bad and it could possibly burn the new sensor. I have been thinking about buying the aftermarket headers and high-flow cat but I noticed these have the downstream sensor hole before the cat! I think that would throw a cel for sure. What would you guys recommend I do? Getting new headers and cat wouldn't be bad considering a couple extra horsies.

[titantn24]

I assume that when you replaced the sensor the first time that you diconnected the battery for an extended period of time to reset. I don't understand what a low voltage code has to do with the cat. Headers aren't a bad idea, but is a high-flow cat necessary? If so, then find one that puts the O2 sensors in similar positions as your stock parts. Good luck.

[turtlecrxsi]

Yes. As stated above you need to reset the ECU. A loose connection will cause the O2 sensor code. I had this problem with my CRX. But in an obd0 car it didn't make much difference except piss me off. Solder the wire and clear the code and you should be good to go. By the way, the Bosch part is the same one as the Honda OEM but Honda's is $150 more.

[honda_luvr_2000]

p0137 has nothing to do with the cat. sensor 2 low voltage is a bad o2 sensor heater circuit.
aftermarket high-flow cats (the real ones) still are a 50/50 chance of turning the cel on for a bad cat. they are on the edge of efficiency and "go bad" a lot quicker than a factory cat.
not to be an ass but... where are u gonna put the second header? u can only fit one header on u'r car since it only has one bank.
wut kinda civic is it? ex, dx, lx, si...
if it's a dx/lx their exhaust system is set up a lot different. the cat is part of the factory exhaust manifold. if u do buy an aftermarket header for a dx/lx then u will have to buy a cat too. u might be able to use a factory cat from an ex/si. not sure exactly how it would meet up w/ the b-pipe in either case, haven't had to deal w/ that yet. also u will have to lengthen the wire harnesses for both o2 sensors since u will be relocating them in relation to the engine.

[yairsaenz83]

Well I installed the new universal Denso sensor. I am 100% sure that the wires were connected correctly. I also disconnected the battery for about 10 minutes to reset the computer. Well this morning, much to my chagrin, the cel came to visit me again!