check engine light...dang

The check engine light comes on when i go into second and just randomly goes on other times. what do i do

Pull back the carpet under the passengers side footwell. then remove the ecu cover. turn the engine on. there will be a little red light blinking. count the number of blinks and refer to a repair manual to diagnose the code.

88-91 Civic ECU Trouble Codes

With the ignition on the ECU will display a single flashing light indicating the system is operating. When the ecu sets a trouble code,the check engine light will come on and the ecu stores the code in the memory. The trouble code will remain in the memory until voltage to the ecu is disconnected. Removing the hazard fuse in the main fuse panel for 10 seconds will reset all trouble codes. Reset the memory after repairs are made. Make sure the ignition is OFF when disconnecting the main fuse.


Code System

Code 1 (1 flash) Oxygen content

Code 3 or 5 Manifold absolute pressure

Code 4 (4 flashes) Crank angle sensor

Code 6 (6 flashes) Coolant temperature

Code 7 (7 flashes) Throttle angle

Code 8 (8 flashes) TDC position (top dead center) timing

Code 9 (9 flashes) No. 1 cylinder position (1.6L)

Code 10 (10 flashes) Intake air temperature

Code 12(12 flashes) No code 11 don't know why. Exhaust gas recirculation system

Code 13 (13 flashes) Atmospheric pressure

Code 14 (14 flashes) Electronic air control (EACV)

Code 15 (15 flashes) Ignition output signal

Code 16 (16 flashes) Fuel injector

Code 17 (17flashes) Vehicle speed sensor

Code 19 (19 flashes) No code 18 for some reason Lock up control solenoid valve

Code 20 (20 flashes) Electric Load