SONOMA, Calif. — The cars driven by Jeff Gordon and Jimmie Johnson failed initial inspection and won't be allowed to practice or qualify Friday for the Nextel Cup race at Infineon Raceway.

The No. 24 and No. 48 Chevrolets had modifications to the front fenders "found to be outside NASCAR tolerances," NASCAR spokesman Ramsey Poston said. No further penalties or suspensions were announced.

Poston said the teams may repair their cars in an effort to pass inspection. Since they are prohibited from qualifying, both cars would have to start from the rear of the 43-car field in Sunday's Toyota/Save Mart 350 if they do meet inspection standards.