I am pleased to report that after many months spent on parts replacements & mixture adjustments, my car passed the first time with the following readings:
NOx limit- 2.00 reading - 1.17
CO limit- 15.0 reading - 6.1
HC limit- .8 reading - .8
As the HC is at the max, are there any suggestions for lowering it? Thanks.

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87 300e (white/black; amg body kit)
88 300ce (red/cream; amg body kit)
93 300ce cabrio (white/blue/blue top)
93 300ce cabrio (black/grey/black top)
98 ml 320 (totaled @ 137,000 miles)
99 clk320 (black/grey/black top)

Hydrocarbons are probably the hardest emissions to control.
Things such as ignition components ( misfires ), the slightest bit of oil consumption, etc. , will elevate HC's.
If you passed, it may not be worth worrying about it until next time.

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2007 C 230 Sport.

Thanks, Manny. I intentionally changed the oil & filter on Sunday, and I'll monitor consumption carefully now. However, from previous experience I suspect the car burns about 1 quart every 500+ miles, which suggests valve stem seals or valve guides. Unfortunately, I don't know if the POs did either. BTW, I used Quaker State oil formulated for helping valve seals in older engines. We'll see if the xtra $$ was worth it.

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87 300e (white/black; amg body kit)
88 300ce (red/cream; amg body kit)
93 300ce cabrio (white/blue/blue top)
93 300ce cabrio (black/grey/black top)
98 ml 320 (totaled @ 137,000 miles)
99 clk320 (black/grey/black top)

One quart every 500 miles +.
I think you just answered your own question.
With that amount of oil consumption, I'd expect to see 2 - 3 times the " normal " HC count.

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2007 C 230 Sport.

Richard,

Could you please clarify your emissions limits there? Ours in WA are CO 1%, HC 150 PPM

You did not specify units of measure and I am trying to make sense of them. Does your car have an O2 sensor and have you changed it?

Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

Mike, yes the car has an O2 sensor & yes, i changed it. Regarding measurements I will have to check the certificate to see if any are specified.

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87 300e (white/black; amg body kit)
88 300ce (red/cream; amg body kit)
93 300ce cabrio (white/blue/blue top)
93 300ce cabrio (black/grey/black top)
98 ml 320 (totaled @ 137,000 miles)
99 clk320 (black/grey/black top)

The I/M 240 test ("Inspection/Maintenance" and the "240" is the length of the full test in seconds, though clean cars will usually terminate early) measures emissions is grams/mile. I/M 240 was developed by the EPA and is the suggested test for non-compliant air quality areas. Setting up a I/M240 test cell is very expensive, so California developed the ASM (acceleration simulation mode) test, which requires much less capital investment and sold it to the EPA.

The ASM test "simulates" acceleration by testing the car at 15 and 25 MPH using more load than is required to maintain speed on a level road, and gas measurements are in PPM (.0001%) and percent.

There is not an exact correlation between I/M 240 emissions and ASM emissions. A car could pass one and fail the other, and I have some issues with the state of California regarding how they select the pass/fail "cutpoints" on the ASM test.

Duke