My 1994 Chevy Astro van failed Cailifonia smog because the HPC measured 61 and the limit is 53. My question is how do I correct it. It was not driven for over a month before the test.
I assume you mean HydroCarbons? I would fill up with premium and drive if for a while but first I would tune it up - new plugs, filters etc. If this does not work you may need a new catalytic converter. California (head slap) is becoming a nightmare. There is a voucher program that might help you out --- http://www.smogtips.com/consumer_assistance.cfm
thanks, will try tune up
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