OBD II Emissions Test Fail

[96RS Alex]

I failed the CT State Emissions Test, my 2002 SLP SS does not see any mileage except for an occasional car show and driven twice a year. Their machine didnt get two items to acknowledge a signal or something, wtf do i know.....i just wanna pass! lol

Any help would be appreciated, I know this is a V6 car forum but most if not all of you have OBDII as daily drivers etc. The test tech rep said I simply gotta run the car longer to expunge the old fuel and return with a fresh 1/2 tank of super and a bottle of STP Dry Gas inside the tank to "clean" the O2 sensors before for the free retest, Is this true? I am ready for a 100 mile thrashing Sunday and I just want to pass!

Below is the test results, advice needed. Prior to the test I replaced the old battery to a brand new Optima Red Top, maybe that had something to do with my test failure but I'm not sure.

[Hib Halverson]

Re: OBD II Emissions Test Fail

The image you posted doesn't show the tailpipe emissions.

If you failed because those 2 readiness flags were not set, no amount of fresh gasoline or "Dry Gas" will set those. They will set after the DTCs which support them pass. The Service Manual explains the emissions test readiness "flags" in detail.

If the car flunked because of it's tailpipe emissions, without knowing what those emissions were and what the standards in CT are, there's not much advice one can offer.

As for "cleaning" oxygen sensors, that's a bunch of crap. If the sensors are lazy or they are "poisoned" there's not much you can do other than replacing them.

What you can do is run a good injector cleaner though the engine which will help if you have a case of injector fouling. Best stuff is Red Line Complete Fuel System Cleaner. Also good is Chevron Techron. Both are detergent-based injector cleaners rather than the more common and cheaper solvent-based products.

Pour in a bottle of Red Line, fill the car with fresh fuel. Drive far enough to run that tank through the engine. Then fill again, and go test. Before you test, make sure you get the cats hot.

[Ibanezz]

If you replaced the battery, it would have cleared your computer. And change alllll your systems from ready to not ready.

Idk about your state but mine (new York) 01 and newer can have 1 not ready, 96-01 can have two. And older than that are pre obd 2 and don't matter.

When I bought my 02 v6 the guy had the battery disconnected so it too cleared my computer. Took some driving to get all but 1 to ready out. It took my around 1000 miles to finally get the last one (catalyst) to finally clear out.

Do some driving and good luck

[Ibanezz]

Oh and the best way to make systems go ready is to do multiple "drive cycles". Each car company is different and GM's is pretty easy. Google it and try that.

[96blackmaro]

Re: OBD II Emissions Test Fail

With Pa if you drive it under 5k miles a year its emission exempt. Not sure if you could look into that.

[96RS Alex]

Re: OBD II Emissions Test Fail

The image you posted doesn't show the tailpipe emissions.

If you failed because those 2 readiness flags were not set, no amount of fresh gasoline or "Dry Gas" will set those. They will set after the DTCs which support them pass. The Service Manual explains the emissions test readiness "flags" in detail.

If the car flunked because of it's tailpipe emissions, without knowing what those emissions were and what the standards in CT are, there's not much advice one can offer.

As for "cleaning" oxygen sensors, that's a bunch of crap. If the sensors are lazy or they are "poisoned" there's not much you can do other than replacing them.

What you can do is run a good injector cleaner though the engine which will help if you have a case of injector fouling. Best stuff is Red Line Complete Fuel System Cleaner. Also good is Chevron Techron. Both are detergent-based injector cleaners rather than the more common and cheaper solvent-based products.

Pour in a bottle of Red Line, fill the car with fresh fuel. Drive far enough to run that tank through the engine. Then fill again, and go test. Before you test, make sure you get the cats hot.

The fail sheet did not show HC CO or NOX readings at all however you are correct about the 2 readiness flags. This is what Im dealing with.

If you replaced the battery, it would have cleared your computer. And change alllll your systems from ready to not ready.

Idk about your state but mine (new York) 01 and newer can have 1 not ready, 96-01 can have two. And older than that are pre obd 2 and don't matter.

When I bought my 02 v6 the guy had the battery disconnected so it too cleared my computer. Took some driving to get all but 1 to ready out. It took my around 1000 miles to finally get the last one (catalyst) to finally clear out.

Do some driving and good luck

Do I disconnect both battery connections or which one for an overnight reset in particular ( + or - )?

Oh and the best way to make systems go ready is to do multiple "drive cycles". Each car company is different and GM's is pretty easy. Google it and try that.

Never heard of a drive cycle, will investigate this.

With Pa if you drive it under 5k miles a year its emission exempt. Not sure if you could look into that.

I will question them for that good point !

Good answers so far to help me out, tomorrows forecasted to rain tho :(

[Rob Bell]

Re: OBD II Emissions Test Fail

Not sure what the Secondary Air System is, but the Evap Emissions System may take a long time to get into a Ready state. I agree with Ibanezz that pulling the battery would have reset everything, and it will take several drive cycles to get everything back to Ready status. Unless you have a way to check the readiness status on your own, I would give it at least a couple of weeks of frequent driving, with no MIL light on, the get EVAP status back to Ready. Let the fuel run down to almost empty, then fill it up. This will probably make it run the EVAP test.

All of those other tests you have on there, that already show ready, are run each time the car starts and go to ready almost immediately. But EVAP only runs under certain conditions.

[Rob Bell]

Re: OBD II Emissions Test Fail

Oh, and you probably won't get tailpipe readings because they just plug in the scanner and look for codes with OBDII. At least here in Illinois they don't test tailpipe emissions any more.

[96RS Alex]

Re: OBD II Emissions Test Fail

I found this on LS1 Tech

http://ls1tech.com/forums/pcm-diagno...odes-dtcs.html

now to figure this all out and what to do about it.

My test center is 10 miles away, I will have to drive the SS much further to satisfy these red flags thrown by computer.

[2.8 Bird]

Re: OBD II Emissions Test Fail

I could wrong but it sounds like a foul fuel to me. My 2.8 didn't run for7 years and when it did I ended up changing the fuel, put 5 fuel cleaners, one for every time I fill up, and I was able to pass emission.

[Ibanezz]

Don't disconnect the battery. It resets your computer. And changes all your systems to not ready. Assuming you've never had any check engine lights, you're systems just have not checked in as ready. And your car won't pass unless they all check in. (Some states allow 1 not ready). Drive cycles create the conditions to make the computer check the systems. Cold start, idle for 2 mins with max electrical load. Accelerate to 55 and cruise at that speed for 3 mins. Then without touching the gas, brake or clutch or gear selector decelerate to 20. Repeat the 55mph for 3 mins and then the decel . That's one drive cycle. Do that a few times and I guarantee you're systems will start checking in as either ready, or throw a check engine light (opposite of ready). But you won't have not readies

[Ibanezz]

http://www.obdii.com/drivecycle.html

Here's the link straight from the obd site. Explains exactly what you do. And how it works. Follow that guide. As you can see in the last step or two. The catalyst is a real a**hole to check in. So it can take a while. But you should be able to pass even if that one doesn't check in assuming your state allows that

[LETZRIDE]

Re: OBD II Emissions Test Fail

if you have hp tuners, go set all the relevant codes to # 3 no error (not just the ones you failed as flashing the pcm will reset all sensors). Scan the car in the vcm, open up the dtc tab and all systems should say ready, if they don't you missed a code...go back and find it, set it to error 3 and repeat until all systems say ready...passed, done.

[96RS Alex]

Re: OBD II Emissions Test Fail

Good morning guys.

Never experimented with HP Tuners, it will be my first foray into the world of tuning and sounds more promising than putting needless miles on my garage queen.

I will look into tutorials and drive the SS to perform some drive cycles under load to achieve a PASS status. Will post my results soon.

[ssms5411]

Re: OBD II Emissions Test Fail

Hptuners is pretty basic , just click and go , good luck with the emissions.