My '95 G20 had a dealer inspection in Nov. Plugs were changed at 37k miles, currently car has 57k. I had a smog check last week here in CA and on one section, I barley passed. One member suggested cleaning the throttle body...the website suggested a can of Gumout first into the intake manifold.

Any other tips for better emissions? Specificlly, my HC needs to come down.