Emissions way off, looking for problem (long) ... (archive)

Yesterday we put my 535is on the emissions machine in an effort to get the gremlins worked out. The car had crapped out real bad the previous day, to the point where it was undriveable... turned out the 02 sensor had gone south. After unplugging the sensor, and changing the plugs, rotor and distributor cap (all of which were worn), the car ran a lot better on the road, but wouldn't idle worth a darn.

Well, on the machine, it was WAY rich initially (7.xx on the CO reading). We got it down to the 0.20 range (whereas it should be in the 0.06 range), but it wouldn't go any lower without killing the idle completely. Also, CO2 never got above 13, whereas it should be up in the 16 range, I believe.

Question: could the car have a burnt or sticking valve to give these symptoms? We'll probably do a compression check Monday or Tuesday, in the hopes of getting more info. For now, it's running, but idling poorly. And I suspect that power is down too.

Any suggestions would be appreciated.
Ken

Follow Ups:

what was the HC and NOX reading? idle or 2000 rpm' dirtydave 22:58 3/31/2002 (0)

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