98 LS1 with Vortec V-9 aftercooler unit.

Smog nimbies said it passed emissions.

My "system malfunction light" has no data so it failed.

I have been resetting my SES a lot lately.

Several codes coming up.

P0420 Catalyst out of range.
P0152 High voltage to o2 sensor.
Misfire cylander 5.

Local tech shop told me to change o2 sensors and put new plug wires and plug on misfiring cylander5.

I am doing this this week.

I also tryed resetting my system back to the factory settings via the superchips programmer supplied by Vortec.

That test was worse.

It showed 5 functions with no data (o2 sensor/02 heater etc.)

Any advise would be greatly appreciated.

Thanks,

Brett

 

you have to go through the drive cycle and let the computer do all its tests. Drive it for like 60 miles of mixed and highway driving


I am in the same boat right now. Mine did all the tests but has not done the o2 test.