Mother

My car (2000 996 manual) goes in for dyno testing using a Mustang Dyno and need to take O2 readings and was wondering if my cats have an extra hole in the pipe for a wideband sensor that can be used. I think I recall seeing a plug in one of them awhile back.

logray

IIRC the small port you are talking about is the backpressure test port.

During testing, a wideband O2 sensor could replace the O2 sensor you already have in place today...

I'm surprised with your FI you aren't already running one to monitor your AFR...

http://www.pelicanparts.com/catalog/...FULmot_pg7.htm

RoW cars would have extra ports pre or post cat avail that are bunged b/c they run fewer O2 sensors.

Mother

If I remove the stock O2 sensor to insert a wideband for testing would that not make my car run worse during testing? I was just trying to figure out how these dyno's get a good wideband O2 reading without welding in a bungie and was hoping the backpressure test port would work temporarily. At this point I can just use my nose as my AFR and man is it rich. In my opinion I think I can use my Durametric and log (stock narrowband O2's) during testing and comparing to the dyno readouts for future tune readings once the car is in tune I do not see the reason to keep looking at a gauge. Although the gauge is enticing.

logray

From the WEVO IV install manual...

For temporary use during dyno tuning, you can
mount the Bosch wide-band sensors in place of
the original equipment rear oxygen sensors (after
the catalytic converter). You can also use sniffers
in the tailpipe. For permanent mounting, 18 x 1.5
mm weld nuta must be welded onto the exhaust
pipe.

redridge

another option is to splice into the sensor... thats what the AFR do.

Mother

I know they plan to use sniffers for the AFR and longray since I know next to nothing on cats ...it's interesting that they recommend mounting the wideband after the cat? Great info guys saves me a few bucks.

Mother

Unfortunately I cannot even see the O2 sensor wires anymore with the SC in the way.