No Communication with OBD when running, HELP!!!
 

We have a 2000 A4 Quattro we cannot smog. Several mechanics have hooked it up to their scanners with no problems. NONE of the smog places (California) are able to however since it won't communicate with their systems WHEN the car is running. Our mechanic (audi specialist) simply can't figure out the problem and has given up. We are at a loss of what to do at this point. The codes are all fine and the car would normally pass smog, took it to the referee who said they won't pass it either even though the codes read fine when not running. Anyone have ideas? Thanks.