ok, so I bought the megan racing headers, and the hole for the 02 sensor was too far away. so I spliced the 02 sensor wiring to make it longer.

the problem.. it seemed to work great for alittle bit. but then the service light went off and when I read the code it threw.. it said I was getting low voltage to the 02 sensor ( but it was thrown as a problem that didnt happen much) so I erased the code and 500 miles later it still hasnt come back on.. BUT I noticed my gas mileage is low (which I figure could definately be a problem having to do with the airfuel mixtures.. blah blah.. anyways, if I was still having the problem why hasnt the light come back on? I mean.. my gas mileage is absolutely horrible right now... any ideas? help????

thanks

 

Is the wire still intact? How many miles on it? (maybe fried o2 sensor?)

 

ya when I checked the wire it still intact.. I figured it COULD be that mabye the wire I spliced in with was too thick but its a pretty similar guage so I dunno.. I hope I didnt fry the o2 sensor.. those things are expensive

 

How'd you check the wire? Just not see it visibly separated? Did you solder the wires together or twist them? Gauge shouldn't matter.

OBD testers can read the sensor voltage, can't they? Could try that.

Could be something unrelated. Detonation pulling timing? Bad fuel (change stations?) Wrong grade? Tire pressures off?
Even dragging brakes
https://www.northamericanmotoring.co...bad+mileage%22

What was the before/after mileage?

 

or bypass valve not closing?
https://www.northamericanmotoring.co...bad+mileage%22

 

im doubting its dragging brakes.. because my car has no signs of drag and definatley isnt having issues accelerating..

the bypass valve not closing is interesting.. as far as fuel I havnt changed anything.. I twisted and crimped. made sure proper colors and all. I have yet to take it apart and redo the wiring because the light has not come back on (and I havnt had much time with finals and all)

im waiting till my next fillup to see the new mileage.. all I know is I went from a complete full tank.. to a quarter tank in around 50 miles.

 

oh. on a second note im noticing I have an exhaust leak on the ol' magnaflow. one of the welds has come undone.. I havnt heard of having an exhaust leak hurt gas mileage.. but could that be it?

 

I don't think Coopers have a BPV.

REDO the wiring. If the signal is within the acceptable range, you may not get a code.

 

Definitely a REDO, and SOLDER the splice.

 

alright thanks