I've noticed my cam sensor is retarded 12 degrees according to the scanner. I don't know what the threshold is for setting the code, but it's obviously higher than that. If you've exceeded the threshold, I'd say you have a mechanical issue that needs to be corrected. As others have said, timing chain stretch can cause this problem, or perhaps the distributor wasn't timed properly the last time it was installed. Either way, you will need a scanner of some sort to properly time the distributor. An alternative to get you through emissions, that I don't recommend, would be the guess and check method of moving the distributor a little bit, clearing the code and seeing if it returns. Repeat until the light doesn't come back. Mark your starting position and If it starts running bad, you probably went the wrong way and you need to stop and back up. I would expect that most vehicles built in 1999 would have high enough mileage and enough timing chain stretch to justify replacement. If you do replace the chain, be sure to order a new timing cover. They are not meant to be reused.