How do I test the main relay on my 92 civic? My car will not start and I took the back seat out and could not hear the fuel pump running when I turn the key so I jumped the relay and I could here the fuel pump running. I purchased a new relay from napa and I installed itand it still did not start. Once again I jumped the relay and I could here the fuel pump running.

 

When you turn the key on (do not crank engine, just turn key on), the check engine light on the dash should light up for about 2 seconds and then go out. The fuel pump should also run while the light is on and then stop when it goes out. You will hear the main relay click on and off. If your engine light doesn't do that, check for power reaching the ECM or as a long shot, fautly ECM (It's almost always something else, not the ECM).

 

To check your main relay: google "Mark Lamond Main Relay" and click on the first link that comes up. Good pictures and it shows you what bad solder points look like.


Good luck.