Smog check - questions.

California smog checks sniff for CO, HC, and NOx at 15mph and 25mph on rollers (the older style smog check does only CO and HC at idle and 2500rpm in neutral). Ignition timing, visual check (for things like check engine lights), and fuel cap are checked.

Seems that test-only stations have less incentive to deliberately cause failures (especially if they offer "pass or retest free") since they won't get any repair business generated by failures (and may not get retest business since a "gold shield" smog repair place can do the retest after repair). But test-only stations tend to be more expensive.

Are you worried it won`t pass? If you are,I have a few easy things to do that will make it pass.

I don't think so.

Nevertheless, what would these easy things be? They might help..

Thanks in advance.