I have a 1990 190e 2.6 and the car failed CA emissions last weekend. Please see below for results:

15mph RPM-1630 CO2%-15.4 O2%-0.65 HC(PPM) MAX-114 AVE-31 MEAS-176(FAILED); CO% MAX-0.73 AVE-0.10 MEAS-0.21(PASS); NO (PPM) MAX-785 AVE-237 MEAS-288(PASS)

25mph RPM-1702 CO2%-15.50 O2%-0.00 HC(PPM) MAX-88 AVE-20 MEAS-105(FAILED); CO% MAX-0.61 AVE-0.09 MEAS-0.13(PASS); NO (PPM) MAX-724 AVE-199 MEAS-78(PASS)

Does anyone know how to interpret these results? Is it bad? Do I need a new Catalytic Converter? I will be changing the plugs, distributor cap, rotor and perform an oil change. Anything else I need to do? I appreciate any assistance. Thanks!

Excessive HC readings are almost a result of misfires. Secondary ignition is the most likely cause.

Also can be caused if the engine oil is contaminated with fuel.

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Sorry, I'm a newbie on all of these things. How do I best remedy the situation with the misfires and the secondary ignition issue. I'm assuming changing the plugs will fix the issue. Do you think I need the change the ignition wires too? Thanks!

Yes! I finally passed the smog test and thanks to this forum, I learned a lot about my car. Keep up the good work!

What I did? Oil change, Spark Plugs (hard to find and was expensive at the dealer), Distributor Cap, Rotor and for safe measure "Guaranteed to Pass". The spark plug wires were still good by checking the resistance - again, thanks to a post on this forum!