OBD2 Readiness, P0420

Okay, so I have a high flow cat, which has no angled bung, and it throws P0420. No problem, disable right? Well, 2 years later, it is time for emissions, and since I have it disabled, apparently that means the OBD2 test will never complete, from what I gather.

I think this is also preventing the cat status from going ready too, and I am only allowed 1 monitor to be in the not ready state. My evap is also currently not ready, which is likely my own fault since I disconnected the battery to check on a wheel sensor issue.

So, what are other people doing to deal with this? I just need to know if I need to throw my stock DP on, and go with a stock tune. What a PITA if that is the case, but I'll do that if I need to. There doesn't seem to be the option for "No error reported" like in other ECUs.

Post tune file

Attached

I have seen a couple of these files before but have not dealt with them.
I would try different settings to see if there is one like the older 3 - do not report

PM sent.

Sorry, I'm used to everyone talking LNF on this forum. I forget there are other engine types on this subforum.

Gonna another local LNF that I tuned to see what his readiness states are. If his set, I'll just keep trying to do the damn readiness procedure.

im running a catless dp on my sky rl with no codes disabled and no codes thrown. :) o2 extender FTW!

I didnt think the P0420 diabled would throw a code. A LSJ I have tuned, along with mine, has gone through emissions with no problems.

I checked another car I tuned around here, and it does go ready eventually, so I guess it's back to driving. Thanks folks.

if u disable a code to dnr your emissions will never completely finish.
i have a dnr rear o2 for my catless dp and everytime i check the readiness the catalyst will never complete but everything else will.

It's set to disable, option 0. It set O2 readiness on the car I tuned, despite the fact that I disabled it, which surprised me, but also made me quite happy. Saves me from having to swap the stock DP in.

Yea thats awesome its gonna pass emissions. Must not be in ca that's for sure

Quote:

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Originally Posted by Wangspeed

It's set to disable, option 0. It set O2 readiness on the car I tuned, despite the fact that I disabled it, which surprised me, but also made me quite happy. Saves me from having to swap the stock DP in.

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That's what my '08 did also, but I had to pass a visual as well so the stock DP went on for a week every two years.

Quote:

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Originally Posted by Iam Broke

That's what my '08 did also, but I had to pass a visual as well so the stock DP went on for a week every two years.

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So as long as there is no visual inspection,
Let say you removed all emissions like rear o2 evap etc etc
Setting Dtc to 0 will have the rediness test report that it ran and passed?

no it reports that that system is not installed which will raise a flag in the federal computers therfore you fail.
most smog shops following the new 50 state have to verify catalyst installation with a visual inspection so again most people fail there too as im sure iambroke avoided with the factory swap every 2 years. iirc from the ca smog license info board that externders are not allowed either so if the guy knows what hes doing anyone with a fake look a like cat will fail at the sight of a rear o2 extender, but its been almost a year since ive researched that with the smog boards. could have changed by now stupid cali and their retarded smog and taxes

On the other OS if you set to IIRC 3 do not report, then scanned with Tech2 and looked at IM readiness test, they would report as Ran and Passed.

So with these OS' there is no such setting?

(it seems there way more settings for this OS like 21 etc)

I dunno why some of you guys don't believe me. I'll post a SS after it sets. Pick option 0 - Disable. It set every OBD2 readiness monitor to Ready state.

Quote:

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Originally Posted by Wangspeed

I dunno why some of you guys don't believe me. I'll post a SS after it sets. Pick option 0 - Disable. It set every OBD2 readiness monitor to Ready state.

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That's what mine did Wang, if I still had it I'd post it also. Maybe it was an early '08 thing. I had one of the XX vin lot (early production test run).

good guess but i got 1st ss in socal for 08 and the first three months were the test run vins so i dont we are that special lol
i tell you what though i havent had a reflash for about three weeks now so ill scan it today and post it.

Never said it was special, just looking for a difference. Mfg ~Mar '08 but I have the exact date at home somewhere. Wasn't released for shipment until July.

The first lots sat in OH until they were released. Yours may be younger? IDK.

VIN was ...XX87297040

R.I.P.

i have an x4873
i think i might actually be after

I've been out of town, so I haven't been able to drive it to set it, which sucks, because my registration just expired.

Mine did not set just checked

Which codes did you set to 0? I think mine is only disabling P0420. Maybe the P013* codes. I don't recall off the top of my head now. Not on a computer w/ HPT.

Sensor 2 voltage and performance codes

I threw in the towel. It must be different on the 09 ECUs. Mine would never go ready for cat state. Went back to stock DP and a tune with P0420 enabled to get it past emissions.

Winning jk

Bumping an old thread here...so is the general consensus that you can get a 2008 to pass with P0420 (but nothing else) disabled, however 09+ need to have all DTC's enabled?

2005 Cavalier 2.2 Ecotec. Added a wideband O2 that bypassed the ECM O2 heater, P0135 DTC. I disabled the by unchecking the SES Enable. Readyness was not check for this on the emission test. I also have always gotten a P0420 in stop and go traffic on the hi-way since it was about 2 years old. This is with the stock, replacement or no cat. I bumped it up from "0 - MIL on first Error" to "1 - MIL on Second Error". That issue went away and I pass emission testing.

I have to conclude that disabling the DTC tells the ECM not to check that circuit and so the inspector does not know its there.