The test sequence applicable when augmenting the emission models through vehicle testing is as follows:

(a) Prepare vehicles per §80.50.

(b) Initial preconditioning per §80.52(a)(1). Vehicles shall be refueled randomly with the fuels required in §80.49 when testing to augment the complex emission model.

(c) Exhaust emissions tests, dynamometer procedure per 40 CFR 86.137-90 with:

(1) Exhaust Benzene and 1,3-Butadiene emissions measured per §80.55; and

(2) Formaldehyde and Acetelaldehyde emissions measured per §80.56.