Rear O2 Code After Installing a Spacer? (Look inside for a bonus boost question!)

[16vCorey]

Can a rear O2 be pulled out of the exhaust flow too much? About tree weeks ago I installed an 034 HFC with a rear O2 spacer. I bought them used from a member here, and the O2 spacer looks kind of home-made, and slightly longer than the 034 spacer. Anyway, last night my CEL popped on, and these are the codes I got.

16524 - Oxygen (Lambda) Sensor B1 S2
P0140 - 004 - No Activity - Intermittent - MIL ON
16523 - Oxygen (Lambda) Sensor B1 S2
P0139 - 004 - Response too Slow - Intermittent

Can the lack of activity and slow response be from it being pulled too far out of the exhaust stream, or is my sensor just dying. It seems awfully coincidental that it's been fine all this time, then decides to die right after I change the cat and install an O2 spacer.



Also, is a "17963 - Charge Pressure P1555 - 001 - Maximum Limit Exceeded - Intermittent" code normal for a car with a stage 1+ tune? It would make sense to me that it would throw that code, since it's seeing more boost than the car was designed to see.

[maurizio]

Could be both.
add a little steel wool. You will still have codes stored but it shouldnt turn on your check engine light.

[Human Garbage]

My vote is for sensor dying. If it was the spacer it would have thrown that code much sooner IMHO.

And no, that charge pressure limit exceeded is not normal for a Stg. 1+ tune (at least not the APR that I have). Something is up with that for sure...

[MikTip]

It highly depends on the ECU.

Some are more sensative to the O2 spacers than others...

Mine, no go with 02 spacer.

Tuner cat delete file

[hightime80]

Agreed. When I installed my test pipe instead of messing with spacers I just had it written off. The rear 02 isnt a wideband anyway so it doesnt effect performance. Send ole K0mpressed a msg on here and he can do it cheaply and remotely.

[16vCorey]

I'll probably have it written out when I upgrade my turbo and get a new tune, but I'm not going to spend the money on it now. The catalytic converter I bought came with a rear O2, so I might swap it and see if anything changes. The wiring is a little longer and the plug is brown instead of black, but other than that I'm pretty sure it will plug in. I guess it's possible that I could have damaged the O2 while installing the HFC. It did get banged around a little while I was guiding the downpipe/hfc back in. I think I'll start a new thread on the boost issue. Thanks all!

[16vCorey]

So the "16524 - Oxygen (Lambda) Sensor B1 S2 P0140 - 004 - No Activity - Intermittent - MIL ON" came back two days after clearing it, so I guess that rules out the cat/spacer as being the cause, since it didn't show up until three weeks or so after the installation. I swapped in the sensor that came with the cat yesterday and cleared the code, so we'll see what happens.

[MikTip]

Funny...chip tuners offer the rear 02 sensor delete file...I wonder why....Hmmmmm....