Hi all,
I purchased a 944 recently and can't get it to pass smog for registration. Yes, I know it's the sellers responsibility. Suffice to say, it's mine now (It's a long story). Here are where things stand. I can get the car to pass at 15mph but at 25 it fails nox. If I adjust so that it passes at 25, it fails CO and HO at 15.
The car runs beautifully.
The plugs are great.
The car has a new CAT installed before I bought it. It's shiny and good looking but who knows, maybe thats the culprit?
I've replaced the 02 sensor.
I've changed the oil and filter
I've tried 91 fuel and 89.
I've tried adding alcohol.
I've tried adjusting the Fuel Quality Switch to -4 fuel. I've also tired it at -4 fuel and -4 timing. It's now back at setting 0. The car continues to run fine, but still won't pass.
I've adjusted the MAF to various setting.
The MAF is sealed tight but I don't know if its been opened.
Lastly, I've left it at a shop with a smog dyno and a mech who works at the Porsche dealership...he can't find a setting where the numbers are right either. His next step was to replace the ECU, not because he knew it would fix things, but hoped by throwing one at it, it might. I told him I could do that, button it up.
Help.
Please for the love of Zuffenhausen...help.
Mark and Kari