My car misfires, idles poorly, runs rich and it failed emission - please help!

[Fred L]

Hello,

I recently bought an 1991 se-r and it idles poorly and it runs rich. As
well, it misfires from the idle all the way up the RPM. As I hold the gas to
2000 RPM, it will constantly misfire and the same goes for higher RPM range.
The poor idle must be due to this misfiring as well. Not surprisingly, the
car didn't pass the emissions. Very hi HC reading.

I've changed the O2 sensor, spark plugs to NGK BKR6E gapped to specs,
cleaned trottlebody, cleaned airfilter. So far it's not solving the problem.
The car has stock timing. What could be wrong with my car?

BTW, when I rev this car, I think I see some darker smoke out the tail pipe.
It's not thick smoke but it's either grey or grey/blue. I'm hoping that it's
just fuel since I smell gas and the car runs rich. There is black smoke-dust
on the rear-bumber just above the muffler. Is this from running too rich?
Or, is my engine burning oil past the rings? Does a car misfire like mine
when it burns oil through the rings?

Please help me solve this problem.