It depends upon the build date of your car. If it was built prior to June 1st, 1992 (1993 model year), it will only have one cam/crank sensor. If it was built after that date, it will have separate crank and cam sensors, both will be on the driver side of the engine. There would only be two sensors max though, not three.
http://www.stealth316.com/2-cas_conversion.htm More information about the differences can be found here. Both of my cars have the crank/cam sensor combo and I don't really know that much about them after they changed. I have also never found any ways to check them on the web or my manual, ohms tests or otherwise.

You said you changed the cap...DOHC engines do not have a distributor cap. What exactly did you replace?

 

http://www.stealth316.com/2-diagcodes91-93.htm

Check the ECU codes. It's worth a shot.