02 sensor question

[Blown240sx]

for some reason my car will not run right with he 02 sensor plugged in on the downpipe of the sr20 redtop motor.

At first I thought it may be a bad 02 sensor so I bought a new one and wired it to color and put it in and it still ran th same. It idles rough, the car wont hold constant speed (you have to either excellerate or decellerate) if you hold it at constant speed the car acks as if it isnt getting gas and begins to stumble and stall out.

But the car runs fine without the O2 sensor plugged in... But I dont know if this is hurting the car or not because the ECU isnt getting a 02 signal.

Is this a wiring issue or has someone installed a 02 eliminator that might cause this problem?

Also I reset the ECU to see if that was the problem and it acted the same as before with the 02 sensor plugged in.

[Ni2s4s0aSnX]

Your problem sounds like what would happen when the O2 sensor wasn't plugged in, normally. I can't think of anything right now that would be usegul, sorry.

[Zero260]

most of the time a new o2 sensor needs "burn time", which means you just run w/ that way for a few days, and the computer learns the fuel curve w/ the new sensor. last time I replaced 1, I had bad gas milage, I put new 1 in, and it took 3 days for the gas milage to return to normal.

[Blown240sx]

Gasmilage isnt my problem

This happend with the old O2 sensor and the new O2 sensor.

The car with th O2 sensor plugged in wont run right. It stumbles at Idle and will stall out. Ad while driving if you keep the car at a constant RPM it will stall out or stumble also. It acts as if its flooding itself or not getting spark.

With the O2 sensor unplugged it runs fine. But I feel its putting the ECU in LIMP mode with cant be good running 12 PSI.

[Zero260]

check the harness for the O2 sensor on the computer side, I had one that had a wire fraying out of the harness, it's worth a shot to look.

[Blown240sx]

Zero I did happen to pull back the taping on the Comp side of th O2 sensor coupler and Noticed my wires had been switch on that side. Instead of the order of

Ground Signal Power ------ Like it should be

Signal Ground Power ------ Is how mine was wired up

So I rewired the O2 sensor and it runs great. No more leaning out at 12 psi now.