I did a search and found an old topic on this but it was really old so I thought I'd see if there is some updated info out there.

Whenever I mash the gas I get a sulfuric smell :? . Only during WOT no other time. Now the old post I read said it could be either a bad CC or worse a failing UIM. I just replaced the motor no more than a year ago and have been planning to get a highflow cat and magnaflow exaust. Should this smell facilitate the purchase of the exaust upgrades or do I have more of a problem here?

Actually, it'* likely a failing O2 sensor causing the engine to run too rich, thus burning in the cat. If you replace it, the only thing I would suggest is *NOT* to use Bosch, and use AC Delco.

If you run for too long with a bad sensor, you'll eventually plug your cat, so you'll want to get that changed when you can.

On the UIM causing that...I'm not familiar with that. A UIM failure will actually cause sweet smelling exhaust as coolant is burned.

Thanks!

By the way do I have one or two sensors? If I have two which should I change before or after cat?

Before the cat

Before you change a sensor and spend the money. You'll want to get a scan tool on to ensure if the sensor is working properly. If so, then your problem is most likely only a catalytic. However the cat doesn't usually go bad on it'* own.

driverjohn2005 has a scantool for your car, but I'm not sure if he has the 94/95 cable. He'* in Bonney Lake.

Thanks!

John was kind enough to loan me his scan tool but the cable doesn't match. Does anyone have any idea where I can get one?? By the way this is what my hookup looks like.



Sorry about the quality

That'* why I told you I wasn't sure if he had the right cable. He has the OBD1 connector, you have the OBD2 connector but your PCM is OBD1 protocol.

You need a 94/95 cable.