My '95 sable failed emissions on the HC twice. The rest of the numbers are okay. The HC numbers are:
The max allowable numbers are:
I did what I could to get it fully warmed up at test time, but it ended up sitting there for about 15 mins before the actual test. There are some smells that suggest combustion problems. It's never really been all that fuel-efficient since I acquired it which was about a year ago. I'll start going through the usual suspects, but one thing I'm wondering about is whether there might be a fuel system problem in the ECU.
The other numbers are fairly high as well, so your catalytic convertors are probably not working very well. But HC are still really high so you have some sort of combustion problem (running a bit rich).
You mentioned a dirty air filter, so I would replace that and clean the MAF. You might also think about changing the oxygen sensors?
Did you get around to running the OBD self-test yet to see if you have any codes?
I installed a new air filter. I think the air filter housing was not attached correctly. An image is attached showing where there might have been a leak (right in the center of the picture). It's hard to tell from the manuals how it sets up exactly. I think I've set it up correctly, but now the metal clips are a little loose. Also, are all models supposed to have an air intake resonator? There isn't one in this vehicle.
There may be some codes in the vehicle. The EEC terminal plastic is warped/ melted. My digital multimeter fluctuated when probing terminal #4, but nothing from the analog multimeter. I know the CEL is working, because it came on a number of times when I happened to leave the MAF sensor connector out one time several weeks ago.
Well, I would have a look at the EGR pressure sensor. Make sure the tubes are attached, aren't cracked, and the sensor isn't melted. Also make sure the EGR valve is working by applying vacuum and listening for the engine to stumble (it should practically stall at idle).
VSS code says signal is too "small" so not sure if that means the sensor is bad, disconnected, or the wires are damaged.
Do you know which codes were on demand and which ones were memory?