are smog test supposed to make you nervous?
 

holy crap! took my 10 year old pickup in to get smogged. i got cocky and simply drove the rig around the corner, no warmup. hell, i do meticulous maintenence. fresh oil, fresh mini tuneup....it felt like i was at the principles office! i barely passed! HC was 47, with max allowable 50! i am thinking my O2 sensor, or cat is on the way out. motor only has 47k miles, but the exhaust system has 100k. two years to ponder my next move...

what bumps up HC?

Being nervous will do it.

Your cat probably wasn't warmed up. You should know that it doesn't start working until it is at operating tempurature. That's why you always drive around first.

My 944 passes with no cat. I still warm it up, though.

What is smog testing?

Uhh....HC's have nothing to do with the cat. HC's are unburned fuel, right?

I thought NOx was taken care of by the cat.

And all this time I thought the cat was for getting rid of _mice_. My bad.

i thought you had dog problems?

On systems with a cat I wouldn't trust the results of a test until the cat was up to operating tempurature. But that being said I think you're right. HCs are unburnt fuel - but if the car wasn't at operating temp then it wasn't operating at it's operating temp and thus not likely burning all of the fuel. Take for example my '80SC - I have a rudementary understanding so bear with me and forgive me if I'm wrong but feel free to correct. The warm up regulator regulates the fuel flow such that it is richer when cold. But this also causes there to be more unburnt fuel...or something like that...

I'm scared of smog tests too.

blue, i think you are right. i really dont know that much about cars....my neighbor, thinks it is my O2 sensor. whatever, i got two years for this truck, and one for my SC.