GT3 wont pass smog

[ferdsgt3rs]

Is it true what I've hears about remapping an ECU that it can cause a car to not pass due to a number of reasons. It's a GT3 2004
I've tried a the full exhaust change etc.....

[JFP in PA]

Originally Posted by ferdsgt3rs

Is it true what I've hears about remapping an ECU that it can cause a car to not pass due to a number of reasons. It's a GT3 2004
I've tried a the full exhaust change etc.....

Yes. Some re-flashes are worse than others in this respect.

[cdrik915]

The re-mapping is for sure guilty , if there is no lambda defaults on the piwi.

[Integral]

can you reflash back to stock? that's what i do on my 996tt every 2 years...

reflash to stock>>drive ~100mi>>get smogged>>reflash back to tune.

[spyerx]

It would pass with a tune unless your OEM indicators are set disabled. Typically tunes will disable check for o2 sensors and if those are inactive it will fail smog.

My 997rs i have a Cobb and can go back to stock easily even though the standard tune keeps o2 enabled and will pass fine.

You can get a simple odbii reader and check these yourself.

[ferdsgt3rs]

After 1.5 years 2 PORSHE dealers a very good tech I know found why the monitors for the cats wouldn't set

the air / fuel ratios were all over the tester very lean / very rich no leaks in the air injection system, crank case pressure correct we looked at the mass air flow it was caked with oily grease, we cleaned the sensor the airflow/ gas mix was within spec
i'm just in amazement the PORSCHE tech couldn't find it. I'm not baggen on the Dealers but process of elimination right?? And the length of time and the $$$$$$
Well any way we did re flash the ECU back to stock, and as I'm told the ECU was chasing the bad AFM as best it could, not good enough to pass smog.

Thanks for all your ideas they helped!!!