He says it almost passed!

2000rpm test just surged, he couldnt get it to stay at 2000rpms. I know Im having fiav issues. May block it before next test.

also can a cat be installed backwards? When I pulled it off the 1g, it was pointing in the other direction. but it dosent fit very well on my car so I reversed it. Would that be my issue?

They stared at my motor for a few minutes.. but didnt say anything about the lack of egr valve, or canister, or anything else thats missing!! Lal

Yes you can put them on backwards. The primary bed is a reduction bed and the secondary bed is an oxidation bed. Install in reverse could potentially have the affect your etest does.

Even if there is no arrows? I been reading that some can be run either way.. but some are 3stage snd cannot.

Im gonna try anyway, as well as start my tune from scratch. I smoothed out the 2000rpm just by playing with the ve tables... so maybe its about time I stsrt over with a new tune.

Well as far I know. 3 way cats replaced 2 way cats in the late 80's. Asuming you are talking about OEM 1g....pretty sure its a 3 way cat.

But getting your tune correct is also an important step.

Its an aftrrmarket 3". Passed sandras etest with it last year.

Then maybe its your tune. Its not a 1g cat its aftermarket.

You failed co most likely tune.

I did upgrade turbo, bigger fuel pump, new filter, and hadthe injectors cleaned.

You should post up a log of Idle and 2500.

Ok.. stock tune reprogrammed. dialed in injectors. fine tuned a little.. sitting at the etest waiting!

Failed again. guess Im flipping the cat around.

How was 2k test ? Are u sure cat is good?

2000 rpm test...
HC-200/201
CO2-1/1.56

Idle test
HC-200/303
CO2- 1/0.96(PASS)

I have no idea the age. but it passed last year on ssndras car.

I would still like to see your idle tune.

Whats on the 1g for tuning?

1g was stock everything.

first test was 3 years of messing around... and no where near stock. second tedt was ecmlink all stock values. aside of injectors amd SD etc.

So possibly your tune is a wee bit off still.

I failed with the 91' added some timing, passed with flying colours. What fuel you running dump some regular in there.

CO is pretty high, how old is your O2 sensor?
I just passed 91 with ECMlink, 1050 injectors etc. Co was .04 at idle, HC read 43, this is from memory I don't have the paper with me.

You are correct all cats are 3 way now but I think it was the early 80s when OEMs were forced to change.

More info.I have the test result form now.
I failed the first test, my O2 was lazy from leaking valve stem seals I suppose so I changed it even though CO was under the 1% limit but HC was well over 200 at both speeds. I installed a used stock type cat, cut and welded 3" pipe onto each end, it was a 2.5". My cat is a Vibrant 200 cell and it had dealt with the same oil from the leaky seals so I wasn't to confident in it doing the job.
I had already done a plug and oil change before the first test.
I made some adjustments to my global and deadtime settings and got my LTFT Lo to nearly "0", STFT was around-2.5. EstAF was 14.6 but the wideband showed 15.2 probably because of a small vac leak I have yet to eliminate in the TB, which was actually causing a lean misfire at 2500. But it was minimal so I tried and passed the test 2nd time with ease.
2500 Idle[which I had set to 1150]
CO .08 .03
HC 47 58
I am guessing the very low CO is because of the vacuum leak because I don't remember it ever being that low in previous tests.

Ok.. bought a new 3" cat.. Gonna swap my br8s out for br6s. Im running a PLX wideband and simutating the narrowband. sensor about 3 years old.

My last etest CO was 0.11 @2500 and 0.01 @idle. With link running SD, MTX WB running NB sim, 680 injectors and an OEM Cat.

Stock CO was 0.01 @2500 and 0.00 @ idle.

I have some logs.. just gotta remember how to drop box

https://www.dropbox.com/s/z4ixftzzbmw80r0/log1.elg?dl=0

This is todays log after warmed up.. some idle... some 2500rpms

then I played a bit with the VE around the 2500 cells and got this.
https://www.dropbox.com/s/btof7lx5hkgi5se/log2.elg?dl=0

Now should I level out the timing during the tests?

Add some methyl hydrate (can tire) into the fuel and give it a good mix before the test. Also, make sure your car is piping hot before sending it in.
Those are some little tricks that helped me pass. Just and idea.

I've found its actually pulling timing back that will lower both HC and CO readings, even 2 degrees will make a big difference (50 ppm or so).

The negative effect this has is raising NOx but luckily they don't test for that anymore .

Methanol also worked for me, had to use a bunch to get results.

Test was done with a fairly beat 3" vibrant weld-on cat.

Legit e-tests seem like wayyy too much of a hassle lol

Jay, I don't know if it is normal for a wideband/sim to cycle that slowly but any stock O2 normally cycles at least once per second in closed loop. Can you try a different sensor?

there is a setting to change in link to get it to cycle like it should i had this issue before.

+1 for what Johnny said. I think I failed with similar numbers as you. A 30 min cruise on the highway and my car went basically right in and it was able to pass. I never had to use meth

Ok.. attempt number 3

FAIL

2500RPM
HC 200/137--pass
CO% 1/1.19--fail

Idle
HC 200/311--FAIL(AND GETTING WORSE??)
CO% 1/1.14

This is new cat, br6 plugs, pulled timing.

Im reallythinking about cheating!

Maybe wire back in my stock 02 sensor.and dumping in some meth.

On problem cars I have blended enough meth to equal e25 and backed off timing to add heat into the exhaust so that the cat runs hotter but my most consistent results have been to install a new O2 if CO is high and a new cat if HC is high. Even a stock narrowband that is lazy from being old or exposed to oil from tired engines can mess up an Etest
Have you passed before using SD?
Also you can idle up to 1250 i think and the highest allowed speed should keep the cat warmer.

Ya.. this car has passed 3 test now with thesame ecu set up. with flying colours. But its a rebiult motor , added 272 cams, tubular header and holset turbo, and Ive swapped the Mtx out for a plx wideband. but the sensor is 3 years old.
I had just noticed my iat is about 108° f.

hmmmmm

Do you have adjustable cam gears? If so spread the cams to reduce overlap. It will smooth your idle and increase vacuum which should lower both CO and HC at both test speeds.

Areyou suggesting my cams might be the ssue?
But no... No adjustable cam gears.

Maybe the cams, the engine is fresh so that should be better for emissions, the ecu setup and tune has passed before. I know guys pass E with big cams but they definitely have an effect on low speed performance and may take some playing.
Do you know anyone with an old exhaust gas analyzer from the older dyno etest equipment. That is how I got mine to pass, we played on an analyzer until I got it right, then drove to the test center and passed.

So I did the wet gas rag on the wideband sensor. Goes from 20.1:1 to 19.1:2 and stays ther. then goes back when removed. Switching simulated readings at 14.7.

I guess all thats left is more tuning and some meth. Just seems it should pass at this point, or be close.

Im stumped and running out of funds... and interest.

Goes from 20.1:1 to 10.1:1



I hate this phone.

your airflowperrev is greater at idle then at 2500.... seems weird.

what size injectors are you running?

Rtm 95lbers
I have always had trouble getting airflowperrev under 30.
IM tthinking og lowering my idle to stock... and leveling out my maps some more.

Also its been suggested to change the Narrow band sim voltage highr which would lean my trims out. To compansate for the big cam overlap.