[tassis]

Does the main relay just control fuel? And If it is getting fuel could it still be bad

[TxGreaseMonkey]

The main relay's full name is the PGM-FI Main Relay (i.e. Program Fuel Injection Main Relay). One relay is energized whenever the ignition is on, which supplies battery voltage to the ECM, power to the fuel injectors, and power for the second relay. The second relay is energized for 2 seconds, when the ignition is switched on, and when the engine is running, which supplies power to the fuel pump.

When main relays go bad, it is usually on an intermittent basis; e.g. in the summer when the temperature soars.

Maybe this will help clarify things for you:

Check Engine Light (CEL) Tests. If the CEL does not go out, most Civics will not spark and the fuel pump will not run. Therefore, all efforts should first be directed to correcting the problem(s) that prevent you from being able to answer "Yes" to the three basic diagnostic questions below:

a. Turning the ignition switch to ON (or position II), not START, does the CEL come on and then go off after 2 seconds? If not, the problem is with the ACG (ALT) (S) 15 amp fuse, in the under-dash fuse/relay box; ECM (perform the K-Test); Main Relay; or the Ignition Switch. Perform tests in that order.

b. When the CEL goes out, do you hear and/or feel the Main Relay "click"? If not, repair or replace the Main Relay.

c. During the 2 second interval that the CEL is on, do you hear the fuel pump in the gas tank run? If not, check that the fuel pump works by jumping terminals 5 and 7 on the main relay connector and then turning the ignition switch to ON.