Any modification to a vehicle's emissions system(s) is cause for it to fail the California smog inspection. The only way to avoid a smog check failure is by receiving approval for the modification from the State Smog Check Referee's office.
In most cases Referee Approvals are only given for engine changes from one size to another, or for upgrading a vehicle's engine to a later year.
You may contact the State Referee's Office at (800) 622-7733.
posted by SmogTips Support
