My new to me 1992 SS came in. I took it to the emission and it failed today. I have no engine light or cel. The car drives fine. I came back took a peak in the engine bay and I noticed the O2 Sensor was not plug in. I plugged it back in, fire up the engine let it idle for a few more minutes. Still no engine light and car seem to run fine. The cat seem to be present as well. I did verify that both engine light is present that lights up when fire up the engine then goes off. Any idea? Thanks.
25/25 test reading allowed HC PPM 125 120 fail CO % 0.68 0.67 fail NOxPPM 1201 848 fail rpm 1543 2500 max co+co2 % 15.1 6.0 min 50/15 HC PPM 144 124 fail CO % 0.81 0.69 fail NOxPPM 822 937 pass rpm 1800 2500 max co+co2 % 15.0 6.0 min
I plugged the O2 sensors back onto the car. I went out for a 20 minutes drive. The 348 drives good with good power, idles at 1000 RPM. No CEL at all, I noticed when I pulled back into the garage and idle for a minute the exhaust fume was much less compared to when it was unplug. Should I take it back for another emission run?
I gonna guess that your cats have been hollowed out. Does the car have a lot of fumes when you do cold start? My 348SS with test pipes will smell on a cold start.
yes, it sounds like it has been hollowed out and I wasn't able to verify with the owner since he is out of the country. I looked at the PPI, it indicated that there might be some work on the cat due to welding spot.
Does it matter if I leave the thermal coupler and o2 sensor plug in? I may need some hyper flow if the cat were indeed hollowed. Hyper flow or New Fabspeed high flow cat?
I live in Texas and my car won't pass with test pipes. I've installed Fab Speed sport cats. This is a simple item to install if you like to work on your car. I still have my original cats, but they have a large baffle on the inlet side that cause a substantial restriction. I'd remove the cats have have a look inside. Other option; some have claimed to pass inspection with aviation fuel.
