If it is a two hole riveted cover
Its a single cam.. it says " 2.0 Split Cam on the cover of the engine... A dual cam would say " 16V Zetec" on the engine cover.
Right side of the engine behind the cam cover.
That would be the flat tappet cam in that engine.
1990 is ka24e, single overhead cam, 1991 is ka24de, dual overhead cam.
Does not have a cam sensor on a 7.3L IDI this engine is not computer controlled.
on front of engine below water pump pully
behind the bottom pulley of the engine
look at the top of the engine you will see the cover is very wide for a twin cam also it is usually maked on the cover DOHC which means double overhead cam
The 1.9 L is a Single Overhead Cam engine. The optional 1.8 L is a Double Overhead Cam engine.
front of engine (the part with the pulleys) under front cover on cam.
On top of the cam sensor synchonizer which is sticking out of the top of the timing cover on the front of the engine.
The cam sensor is located on the left side of the engine (as your looking at it) on the valve cover