I guess potentially, if you had some leaky valve stem seals that was slowed by the HM oil. No other seals in the engine could really affect exhaust emissions though...
They only tailpipe test cars that are model year 99 and older though. Anything 2000 or newer is just a check of obd2 monitors, visual and function test.
My 83 Silverado with the 305 has leaky valve guide seals for the last 25 yrs, smokes on the first start of the day, burns off and your good for the rest of the day, use Pennz High Mileage oil, she's passed all here smog checks, key is a good tuneup and oil change before going in for the test and a HOT engine, take my truck out on the highway and run high speeds for about 10 miles then straight to the smog station, been using Guaranteed to Pass fuel additive in the tank, don't know if it works but hey every little bit helps and she hasn't failed yet.
Originally Posted By: bigj_16
Always change your oil just prior to a smog check
Agreed. I always make sure of this. I remember a friend of mine with his minty IROC Z that he rarely drives failed smog. Had low miles, but oil went bad from sitting too long. Went home & changed the oil & passed SMOG the next day lol