No codes with ZZP off-road downpipe?

[iTurbo]

A couple months ago I installed a ZZP off-road downpipe onto the Regal GS. I reinstalled the rear O2 sensor, but figured I would get a code for sure and probably even a SES light since there is no longer a catalytic converter. So far I still haven't gotten a code and no SES light. I thought for sure I would have to get an O2 emulator but so far I haven't needed one. Strange?

 

And I'm wondering how many O2 sensors are on the L67? I figured there would be three, but I'm only able to 'see' two of them with the Kiwi Wifi and DashCommand app. Both seem to be working great though; bouncing between 0-1v with car idling.

[runt]

I think the L67 is the same as the L36 so there would only be two O2s.

 

I put a ZZP dp on my old GP and had a code within days. But mine also had the "high flow cat" option for local emissions.

 

 

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[jeremy]

is the car tuned? I am betting the code is disabled via the tune, otherwise it should have tripped it. especially with the straight pipe w/o cat....

[9lumina6]

^^ agreed.....for example, if there's a DHP tune in the car....they disable the rear O2 codes I believe.

[iTurbo]

Ack, yes I forgot to mention it does have the ZZP 1.0 PCM tune with P0420, evap, and EGR code deletes. Totally forgot about that part.

 

So I shouldn't ever need an O2 emulator then? Could probably just remove the downstream O2 and put a plug in there, or a wide-band sensor later on?

[jeremy]

just plug it up and call it a day

[GP1138]

I've heard of people using spark plug non-foulers for this purpose.

[9lumina6]

I like the wideband idea best

[GtpKo]

Just plug it for now, without a cat there's no need for downstream O2. Wideband later if you like. They're both functioning as upstream at the moment. I think I still have one of those O2 plugs in my toolbox still...

[Andrew]

i leave mine in place in case of inspections. Wideband 02 would go in the upstream spot since it needs to be as near the engine as possible to read accurately.

[Addicted To Boost]

I have the ZZP 3" downpipe with the high flow cat and the "low catalyst efficiency" code pops up within a couple hours of driving.

[Andrew]

then you need an 02 sim or the code deleted.

[Ramblin Garage]

I have the ZZP 3" downpipe with the high flow cat and the "low catalyst efficiency" code pops up within a couple hours of driving.

 

use a spark plug de-fouler, they work well from what I've seen.

 

http://forums.evolutionm.net/evo-how-requests-questions-tips/114931-how-install-spark-plug-anti-foulers-remove-ses-cel-light.html

[Addicted To Boost]

use a spark plug de-fouler, they work well from what I've seen.

 

http://forums.evolutionm.net/evo-how-requests-questions-tips/114931-how-install-spark-plug-anti-foulers-remove-ses-cel-light.html

Very interesting. I will have to try this.

[Addicted To Boost]

use a spark plug de-fouler, they work well from what I've seen.

 

http://forums.evolutionm.net/evo-how-requests-questions-tips/114931-how-install-spark-plug-anti-foulers-remove-ses-cel-light.html

 

I did this to my GP today... so far, no more check engine light!

 

I bought a package of 2 of them, drilled one out so the O2 will thread all the way in and have a small amount of airspace around it, then threaded the O2 and both of the anti-foulers together and installed them in the exhaust. Pics below:

[alec_b]

Did this trick on my old '99 Caddy after I gutted the cat. Worked like a charm!