O2 sensor

[kevin keener]

Well here it is, my o2 sensor wire connector found its way on the header and nearly melted in two. I pulled all the wires what remained anyway on the o2 side completely out.
The harness side is ok. The question I have is once I removed the 02 sensor completely out of the equation the car still ran good, and even a better idle than before and no check engine light ever came on. How is this possible?

 

[delta448]

Is the car stock? Your profile is blank.
The CEL will come on eventually. The car could be running better right now for many reasons, but I'm guessing that it's going to start running rich very soon during closed loop.

 

[kevin keener]

It is basically stock,14b cheap turbo manifold, JDM bottom end, that's all. I was racing around with it the other day and it seemed slower, but if i remember correctly during wot your basically running in closed loop anyway am i correct.

 

[delta448]

Closed loop is when the ECU is actually using the O2 signal to adjust fuel trims and is only active under normal commuter-esque driving conditions. During wot you'll definitely be in open loop and the ECU will be running straight off of a pre-defined fueling table.

 

[kevin keener]

thanks for the clarification. I can still race around with it being unhooked ,I will just get horrible gas mileage correct?

 

[airmail96]

Very good description delta.

 

[delta448]

Horrible gas mileage, strong smell of unburnt gas in the exhaust, poor idle (likely often stalling out when coming to a stop), the CEL, significant off-boost power loss, and extra crap to clog up your catalytic convertor.

So the harness side is still fine, -it's just the O2 sensor side that melted?

 

[kevin keener]

why would it take so long for the engine light to come on?

 

[delta448]

How much have you driven it? More than a full tank of gas through it? I'm not sure about why yours isn't on yet, but the CEL usually comes and goes for a short while on my car and then once the sensor completely fails it stays on, all within about a half tank of gas.

 

[kevin keener]

I maybe have driven it for 15 miles, thats it since it happend. Yes it is only melted on the 02 sensor side. I must not be driving long enough for it to come on then. can I pm you a question totally off the subject?

 

[delta448]

Sure, but if it's DSM related why not start a new thread and just PM me the link so others can help too.

 

[kevin keener]

thank you for you insight, it has been very enlightening

 

[habitatguy187]

why would it take so long for the engine light to come on?

It's very hard to get a 1g cel to come on for an o2 sensor. There's a small write up on it under vfaqs newbie questions.