Whats up guys

I drive 99 gst and I have recently instaled downpipe with no cat - now my Check Engine Light will come off every now and then becouse of that...
I know that whenyou take out the cat youneed an O2 simulator in place of the rear o2 sensor... but I was wondering if I leave the second o2 sensor just hanging outside (well not just hanging - I would have to secure it somehow) and 'reading' the air outside the exhasut pipe - Will this work? Or will I still be getting the CEL? And if this wouldnt work than please explain why?
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You will still be getting the cel.. Its designed to read the air coming out of the motor.. And since the air "outside" the pipe is nowhere near what comes out of the motor, the sensor will think that something is wrong.. Hence putting your light back on.. My Hardtop is the same way.. You just have to live with the light being on, or you can take the dash gauges out and pull the little light for the CEL...

 

Isn'to2 sensorjust a temperature sensorthat inform when the cat is overheating? (caused by carbon build up in the cat) Doesnt it only lights up CEL above a certain temperature? If I simply cable tie it outside of an exhaust pipe, it will be reading less than its activation temperature so CEL should not come off. Or am I wrong?[/align]

 

There actually is a way to trick the computer into thinking it has the correct o2 reading. Go to your local auto part store and ask for...**** i dont remember what theyre called. Theyre designed to extend your spark plugs away from the block for some odd reason...****..ill get back to you when i remember what theyre called... But you just plug them into your exhaust and plug your sensor into it, and should remove the CEL.

 

Spark plug anti fouler thing.The idea of those is for old *** worn out engines that foul one plug constantly over time, you put them on and it keeps the plug out of the direct oil & crap in the cylinder and they wont foul near as fast.
i know this isnt exactly the same car, but on a neon i just put the 2nd o2 sensor in the pipe in about the same spot as where it was behind the cat and never got a CEL or any problems with how it ran.

 

Get the spark plug fouler. It works fine. We did it on emonz evo and got rid of the CEL. only like a $10-$20 mod . Im surprised no one routed him to our DIY on it
https://mitsubishiforum.com/m_94383/tm.htm

 

hey "theengineer" do you know what the readout was when the vehicle did a smog test (if applicable)?I used to run "mil eliminators" on my cobra to get rid of the CEL, but during smog, it would give a "not ready" reading. TX allowed for 2 not ready readings I don't know about the other states; especially CA.

 

we have yet to bring it to get emmissions done