AVONDALE, Ariz. — The credo in NASCAR has always been “If you ain’t cheatin’, you ain’t tryin’,” and that’s never changed despite serious efforts to keep things on the up-and-up.

Now that culture has resurfaced and at a most inopportune time.

There is one race to go to set the championship field, Sunday in Phoenix, and Kevin Harvick has been snared in the latest scandal. NASCAR found Harvick had an illegal race-winning car – his second of the season – after his victory at Texas Motor Speedway earned him an automatic berth in the Nov. 18 title race in Florida.

The issue was with a spoiler that had been modified to give Harvick an aerodynamic advantage; he dominated and won for a Cup Series-high eighth time this year. How much of an advantage Harvick had is irrelevant: The levels of deceit NASCAR believes Stewart-Haas Racing went to were so devious the intent can’t be questioned.

Once NASCAR had the car back from Texas and in its Research and Development Center, the spoiler was removed and determined not to be the part supplied by the vendor. Instead, NASCAR believes SHR made its own spoiler, passed it off as one from the mandatory vendor and used it to help Harvick win.

The details were unveiled late Wednesday, 10 hours after Harvick’s spot in the finale was revoked. NASCAR has for several years refused to give specifics about infractions – keeping secret ideas on how to game the system – but reversed course on the Harvick penalty because of mounting criticism about the severity of his punishment. Not only did Harvick lose his spot in the final four at Homestead-Miami Speedway, but he must race the final two weeks of the season without his crew chief and car chief.

Scott Miller, NASCAR’s vice president of competition, said SHR took the notion of pushing boundaries and exploring technology “into borderline ridiculous territory.”

With the stakes so high this weekend at Phoenix, where seven drivers will compete for three open spots in the title race, NASCAR will check spoilers at the track.

SHR has not challenged NASCAR’s cheating allegation. The team said it would not appeal.