Hi folks,
My 2003 996 turbo failed it's smog yesterday.
It's got a softronic flash and upgraded divertor vavles, but not other mods.

Idle :
CO2 : 15.3%
O2 : 0%
HC : 7
CO : 0.63%

2500 rpm
CO2 : 14.5%
O2 :0&
HC : 11
CO :1.5% <--- FAIL

No CEL.

It passed two years ago with the same flash.

I hooked up my DashCmd and looked at some stats this morning...
LTFT at about 0.8%
STFT swinging between max's of -20 and +20
ATF ration 13.7 <--- looks like the SoftTronic flash is aiming for 13.7

I looked at my air filter and it looked pretty ugly (my bad !)
Also, this particular tank of gas came from a rotten robbie (had no choice)...

Anyway, I replaced the air filter and reset the ECU and filled it again with tier1 fuel.

I ran it home from work tonight (40+ miles) of horrible traffic and then wide open freeway at high speed. 50/50 I'd say.

I logged the data and have noticed the LTFT is 0.8% and STFT is only moving up and down by 3-4 either way depending on accel/decel.
ATF is still aiming for 13.7 but I think that might be the flash wanting a slightly richer mixture to help with the extra boost ?

The ECU reset and new filter appear to have made a big difference to the drivability. Now I've done it I realize it previously had hesitation on acceleration, but now it seems very wiling, reaches over 1.2 bar and holds it longer than I dare. So, I'm feeling lucky. I'm feeling like popping back to the smog test dudes and getting them to just pre-test it and see what the CO % looks like now !

Am I delusional ?

:-)

I was planning on replacing the O2 sensors (downstream) over the weekend but my O2 sensor order went awry today and I cancelled, hoping to get some locally. I was also planning on looking for vacuum leaks.

What do you guys think ? Do you think a bad filter combined with a tank of bad fuel or am I looking at O2 sensors / MAF / MAP ?

 

I hate to say it, but this isn't the first time I've seen Softronic have smog issues on this board.

MY CIAC tune(s) have passed the sniffer test with flying colors for ~ 7 years now with stock maf, 100 cell cats, and various upgrades up to and including stock, then bigger turbos, hitachi maf, bigger injectors, intercoolers, etc...

 

A very dirty air filter will cause you to have high CO levels at 2500 rpm. I would try again and see what happens.

 

I would suggest that you re check it. A dirty plugged filter etc can affect the CO/HC as an intake leak or Maf issue will also. You can always contact us to check the flash yet you said it passed prior. The software doesn't change yet other factors may have such as the filter that you stated was dirty. In any case the car should pass a smog test.


We have also been stated as failing emissions in other posts yet some of those cars hadn't even had a Softronic flash. They assumed since they bought a flash from a specific dealer it must have been Softronic yet they hadn't been.

 

What I have found seems to work for me -- mainly with a Boxster now with over 254K miles on it (which the reason I'm replying is it just passed CA smog!) -- but also once with my 03 Turbo (stock) is you have to run top tier gasoline.

Running some supermarket grade (not a top tier gas) in the Boxster the CEL can come on from a weak converter. It can come on running top tier gas too but it comes on more readily running the cheaper gas.

In your car's case run a bottle or two of Techron through the tank, following instructions. After the tank with the last bottle of Techron gets low refuel and I like to change the oil/filter too.

Drive the car a lot. I have been covering sometimes 100 miles per day in my Boxster running up and down the highway taking care of a sick family member.

I pick a warm to hot day. I do not turn on the A/C. I drive the car 30 miles or so at highway speeds to get everything nice and warm.

I do not shut off the engine while arranging to have the car smog checked. The smog tech doesn't shut off the engine either. In CA at least they are forbidden to 'super heat' the engine/exhaust system by running the engine rpms up before the test.

Also, if the plugs are due to be changed -- IIRC even the stock Turbo requires new plugs every 30K miles -- change them. I do not know what a dirty filter will do. BTW, just because it looks dirty doesn't mean the filter is interfering with air flow.

But to be safe change it.

Do not overfill the engine with oil and try to have fresh oil in the engine. Fresh oil is less viscous and less likely to add to the HC load the converters have to deal with.

Are the long term fuel trims (1 and 2) about equal? Do the short term fuel trims (1 and 2) general agree with one another?

What about the #2 sensors?

Up to you but before you throw new sensors at the problem it might be worth to do what I suggest above, have the car pre-tested to see if it will pass.

If so, then get it done ASAP.

If not .... without any error codes, and assuming all the supporting readiness monitors are set to complete (if some aren't this might provide a clue as to which component/system/sensor is causing you grief), it is hard to know what's best.

It can get rather expensive throwing MAF, sensors, plugs, coils, trying to tweak things (playing with street gas/race gas (which a smog test tech told me doesn't have any effect on the car's emissions)) and so on.

Sincerely,

Macster.

 

how close are you to passing?

if it was close, you may be fine. otherwise, i would do all the suggested above. you don't want to fail too many times or else you'll be flagged. get one of those guarantee to pass bottles too.

btw, go to another smog shop. some machines work better for some reason.

 

I tried it again this morning and it was a bit better, but still a fail (CO ~ 1.2%).
I relfashed back to the stock ECU and it passed with flying colors (HC = 1 and CO = 0.0%) STFT moving 3-4 either way and LTFT at zero. 14.7% ATF.

I got to say the stock machine feels sluggish now I've gone since 2008 with the Softronic flash !

I think I'll be reflashing in fairly short order !

:-)

 

Maybe looking for a new flash that give better "protection" against smog testing might be a good thing.. Keep us posted..

 

Its interesting that you have had it since 2008 and have passed emissions prior yet not this time... The Co was also 1.5 yesterday and 1.2 today. In any case Softronic does provide the stock file so you can flash back whenever you like. The Short and long term fuel trims as with the other parameters of the DME reset when flashed and then will learn again. This would happen flashing to stock or tuned. The same thing happens if you disconnect the battery. The RKATS will go to 0 and the FRA's will default at 1.00 and then add or subtract fuel after the car has been driven, this though does take a bit and then the basic fuel adjust has to complete at idle also. Your reader seems to show them both at 0 and then corrections + or -. The readings will be different again when you flash back to the tuned file until it learns again in which they will default to in your case 0.

 

+1 One of the nice features of the Softronic is that you can flash back to stock prior to a smog test and you should be fine (unless of course something else is wrong).

 

I too recently had the same problem with really high HCo2 and Co2. I was recommended a bottle of fuel injector cleaner and tried and HCo2 passed but carbon was still high. Then I changed the airfilter and did a sea foam flush and it passed right away. Hope this helps you

 

Got me on that one. What is a sea foam flush?

 

sea foam, I believe is a fuel injection cleaner( not exactly sure). They hooked it up to my fuel system and ran the car for awhile. In the end, it blew out a bunch of black smoke. I then drove it for like 10 miles at high revs(5500-6500rpms) and took it to smog. It was my 3rd time trying and it finally passed. The carbon level dropped by 5-6 pts.