Is there a cut off year to have to seq a car

From the Oregon DEQ website: "DEQ does not require emissions testing of newer model year vehicles because they typically have lower mileage and are therefore less likely to experience problems with their emissions control systems. During calendar year 2019, the following model years qualify as a “Newer Model Year Vehicle” Model Year 2016 (So long as the current registration expires before January 1, 2020)  Model Year 2017 Model Year 2018 Model Year 2019 Model Year 2020" Furthermore, if your car falls into one of the above model years, you can simply renew your registration online at https://www.oregondmv.com/online instead of going anywhere.

Yes. 1974 and older model years do not require deq testing.