We recently acquired a 98 Honda civic GX (natural gas) from a friend. it was making a bad sulfur smell and one time while driving we heard a pop under the hood, and then buzzing under the dashboard, and then the car died. we found out the pop under the hood was the cover of the battery blew off. I think his probably was the cause of the sulfur smell in the car. also we had popping and smoke coming from the radio. We towed the car home and have been trying to fix it. there was a 20 amp fuse in 44 (FI E/M) that was blown. We got a new battery from costco and when plugging it in, upon connecting the battery the condenser fan immediately started running. so we replaced the relay with a new one and that solved that problem. when we turn the key, the lights on the dashboard light up as expected When we turn to position 2 it blows the 44 fuse again. we started troubleshooting. we checked all the fuses and relays under the dash and they look good. next we checked the main relay. we tested it and it seems to work fine. we got a backup from the junkyard and it behaves the same. We next went to the ECM. we discovered through trial and error that if we unplug connector B to the ECM, the fuse does not blow when we turn the key to the second position. but nothing happens when we turn it to the third (start position). I unplugged all the fuel injectors and the Idle Air control valve and it still blows the 44 fuse if the connector b of the ECM is connected. I also unplugged the injector control module and that doesn't seem to have an effect either.

Is my ECM bad, or is there something else I can do to find where the problem might be.

thanks so much for your help.

Will

 

Maybe check all your ground wires.