When it blinked once it is just when it turns on after that is when you start counting...code 16 has to do with fuel injection system..make sure all the plugs are in all they way and get you fuel system cleaned out. The rest of the codes for your car is as follows

1- oxgyen sensor
4- crank shaft position sensor
5- MAP sensor
6- Engine coolant sensor
7- Throttle position sensor
8- TDC sensor
9- CYP sensor
10- Intake air temp. sensor
12- EGR lift sensor
13- BARO sensor
14- Idle air control sensor
15- Ignition output signal
16 - fuel injection system
17- Vehicle speed sensor
20- Electrical load dector
30- Automatic transmission signal A
31- Automatic transmission signal B
41- Primary oxgyen sensor- heater
43- Fuel supply system

that is the codes..some were skipped over because they did not concern the 90 civic...Hope the list helps you in the future..and my advice to any new civic owner...get yourself a helms