1990 Other GMC Models Failed California smog

1990 GMC
246,000 MILES • V8 • 4WD • AUTOMATIC
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LINVDAN
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I just failed CA smog, my HC levels are as such
Idle- RPM- 1062, HC measures 173
2500 RPM- HC measures 400

What should I do to correct this? Truck seems to run fine.
Thanks
Aug 19, 2008 at 6:51 PM
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2CARPRO JACK
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At that mileage, it could very well be the cat converter is all used up. They are a reactive material and will only last so long
Aug 22, 2008 at 12:19 PM