HC=0005.8294
NOX=002.9685

Car is running rough as well, probably because of whatever is causing richness. No SES light.

New:
O2's
Plugs
Wires
EGR
IAC
PCV Valve

Had the car scanned by the dealer. No codes. What do you think?

 

opti, maybe?

 

Sorry, new opti as well. Forgot to add it.

 

How old is the cat???

 

I think it's original, 116,000 miles. Do you think that could cause a roughness as well? If the Cat is bad I would think I would get a SES light from maybe the 02's.

 

Yep, and you wouldn't get a SES code because you don't have rear O2 sensors because your car is OBD-I. May want to check that out.

Tom

 

you would only get a SES on dual cat car if the cats went bad. On single cat cars they can go bad and you don't get a code.

 

Wow, thats good to know, thank you i will check it out.

 

What would happen if I unplugged my O2's. Help or hurt the richness.