The helpful sticker above the relay board on the drivers side in the engine compartment informs me that the correct CO value is 2.0 ±1.0 - and the helpful hint that the value must be measured "upstream of the catalytic converter"/

This is a question for the old-time experts: Did Porsche really expect you to take off the muffler and catalytic converter to measure CO? I can't see a way to do it without disassembling the whole system...

Bunghole.....stick a probe in there.....upstream from the cat.


AW GAWD,,,,,I said probe and bunghole on the same sentence!!!!!!!!!!!!!!!!!!!AHHHHHHHHHHHHHHHHHAaahahahahhahahah, I'm in a Beevus and Butthead sitcom........

There is an opening somewhere? I didn't notice it... where is it?

if you have an 02 sensor...yes. Pull the sensor.

CO test port and cap on the stock exhaust

Umh, the O2-sensor is downstream of the catalytic converter. It's screwed into it, but on the downstream side. I saw that last weekend when the exhaust had to come off for a clutch replacement. That can't be the right place...

Thanks Ed, the exhaust is stock, I just haven't noticed that particular opening