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Need to pass smog. help quick!

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trying to pass a 1985 euro m5 motor, the only thing its failing is HC's at idle (400 ppm) and CO was barely over.

however this was with just a magnaflow bullet cat.

any suggestions are appreciated
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High HC and CO indicates rich fuel mixture... and there's no adjustments you can make on that.

There's a couple of easy things to check:
1) Make sure the engine is warmed up - the ECM runs the motor rich until everything is at normal operating temperature.
2) Clean the spark plugs.

If you're close, perhaps changing gasoline brands to one that has more oxygenates?
does it even seem like its passable though? if i run race gas, clean the plugs, and weld a cat on there?
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