o2 sensor bad? weird problem.....help!?!?

craven · Post by **craven** » Fri Dec 21, 2007 6:12 am

i installed a comptech replica header yesterday....well when i was installing it i cleaned the o2 sensor with carb cleaner.....then when i was installing the header the o2 sensor banged off the tie bara few times (not hard bumped)

then when i turned the car on it started bogging bad and shutting off, almost like a short in the o2 sensor?

well i checked the plugs they were black, and so i turned off closed loop and it idles fine??

so i realized that the o2 sensor is reading 18.1 lamda values and its trying to add fuel, and keeps adding fuel and until it just cuts off flooding the cylinders, but the value wont change it always fluctuates between 15 -20 lamda...

i got a CEL and it said code = ???
primary o2 sensor NO ACTIVITY

that keeps coming on and then eventually stopped and its still reading lamda all over the place...and if i turn off closed loop it runs without stalling but i hit lean cut at 3k and i know its because the header leaned me out and i cant tune it due to impoper o2 readings.....

here is my datalog and my current map so anyone can see what my volts and amps are on the o2 sensor so i can find out if they are incorrect volts and know if its truely fried....

autozone has a bosch primary ordered for me today for 169.00

120 cheaper than dealer....

doug if you could take a look 2 that would be great

thanks

Post by **Hondata** » Fri Dec 21, 2007 10:05 am

I'm assuming that this is a RSX.

I would not recommend using anything other than a stock o2 sensor, especially if there is a problem you're trying to track down.

The datalog shows the o2 sensor working ok. It is a little lean at idle but that is not from the o2 sensor as it is in open loop.

Check that none of the pins in the connectors are bent or damaged. Check the engine grounds are still good. Pull the ECU back into closed loop, and if it stalls then post a datalog.

craven · Post by **craven** » Fri Dec 21, 2007 10:14 am

could it have been when ui bumped it?

i bumped it in the end where the wires were?

if i add fuel everywhere it doesnt matter i ccan add 25% fuel and it still reads above 17 lamda but it will stall due to flooding and probably is in the 10 area at idle or higher....but the sensor is acting really weird....

Post by **Spunkster** » Fri Dec 21, 2007 10:50 am

Using carb cleaner on an oxygen sensor was probably the cause of your problem. You should never try to clean an o2 sensor. It's time to get a new sensor.