So seems like a problem w/primary O2 sensor.
I have a megan header test pipe and tanabe catback w/silencer. The light did not turn on right after I swapped for the aforementioned setup though, took at lieast 4 or 5 months. but i recently put a silencer on....do you think that it could played a role in the CEL? or do you think this more of a leak? anything else?
and meanwhile while i'm drving with the light on i'll be running a lillte rich right?
in any case i'll have to change the O2 sensor?

thanks in advance

 

Remove the silencer ans see what happens. Usually when people install test pipes they get a cel for the secondary o2 sensor.

 

you're right... i forgot to mention that i have the cheater spark plug bung (item # 290070841983 on ebay), and that's why i haven't gotten gotten a CEL for the secondary o2 sensor in the first few months.

when that kind of CEL (61 -Primary Heated Oxygen Circuit) comes on does that usually mean the sensor is fried? or not necessarily, might only mean that there's a flow problem? inconsistensy perhaps?

 

well code 61 means o2 sensor 1, either is getting high voltage, low voltage, or slow response (or obviously, no response). since you're saying it didn't come on right away, chances are the sensor is on it's way out.

if you have a test pipe anyway, you're best bet is to just get the ecu chipped to bypass both o2 sensors instead of spending $150+ on 1 new o2 sensor..when chances are the secondary one's gonna shoot a code pretty soon anyway.

 

how would you chip the ECU? i haven't heard anything about that, unless you mean those MIL resistor-type gimmicks that you insert after splicing the wires right by the sensor itself. i do have an A/F ratio meter that i could perhaps connect to check what's going on with the voltage.

and i'm not worried about the secondary o2 sensor, since i have the cheater plug sensor is pulled out of the direct flow, so it there's a significant diference in voltage output between it and the primary o2 sensor... one of the few small and simple gadgets that actually works well.

and as far as new o2 sensors there go for 55 shipped (Denso 234-4621 for H22A4) so idk where you got the 150+...maybe the dealer rape charge?

 

you can bring it to a place that sockets and actually puts a new chip in the ecu for certain programs that you want ran or not ran. my friend has his ecu chipped for a "stock" 2-step, ignore o2 sensors, upgraded fuel maps and so on and so forth. the right place can chip it for the specific mods you have done to your car.

and i have a '93 lude and i only have 1 o2 sensor that was starting to go..pricing around the cheapest i could fine was a "wire yourself" bosch, at like $85. all the pre-wired ones were quite expensive.

 

the sensor could have been damaged when you removed it for the install, if u dropped it and an end was impacted this could easily cause it to malfunction.

 

good point i did slam a few bumps and i'm pretty damn low on race nuespeeds, i guess i'll have to wait till the shitty weather passes by and get under it to take a look.
thanks inc.

 

if your still getting it, you can use a defouler, which your 02 sensor will plug into then...