Here are some tips to follow. Bring your vehicle to normal operating temperature. A 10-mile drive on the freeway is best. Don't wait in a long line. This may also result in your vehicle failing the test unnecessarily.
Lines tend to be shorter in the middle of the month.
While in line, do not shut off the engine. This helps keep the engine at normal operating temperature. Ecology oversees the operation of the test stations and the Authorized Emission Repair Specialists. Des Moines 22406 Pacific Hwy. Kent 407 Washington Ave.