I just got my '91 Accord running again the other day, started up multiple times just fine. I went to take it to the gas station last night and it wouldn't start. The main relay (actually what I'm guessing is the main relay, a reddish brown box way up under the dash) was making a fast clicking noise sounding like Morse code. The solenoid on the shift lever lock was clicking at the same time as the main relay.

I was finally able to remove the reddish brown box, pulled out the circuit board, and tried reflowing the solder joints on it. Put it back in and still same clicking. The engine cranks just fine, it just never starts.

Any ideas what could be wrong here? Thanks a bunch for any insight!

 

I've been reading about checking all the grounds, but I can't seem to find where the thermostat ground would be. Any help on thise, pics especially,would be very appreciated.

 

Surely someone out there knows where the grounds are? Any other suggestions?

 

I've been playing with it a little more. I turned the key to ACC, when it would normally start the clicking and it was fine. I tried cranking the engine and it wouldn't catch. The battery was almost dead so that may have been why. As soon as I stopped cranking the clicking was at it again. Usually it seems that the first time I put the key in after not trying for a while, it will click after a 2 second pause (after the fuel pump). Any other time after that it will start clicking as soon as you put the key to ACC.

I noticed there was a wire wrapped around the ECU fuse under the dash. I traced it back till it went under the rear seats. Not sure what that was for. The fuse goes in nice and firm, but I did notice the clicking stop after bumping the fuse. I tried starting it and still nothing. It's probably a bad connection, but it seems like it clicks when the connection is good, and doesn't click when it's bad (the fuse completely removed). When the wire was wrapped around the fuse originally, it was shorting both sides of the fuse. Although this presents no electrical problem, it wouldn't offer any over current protection. The clicking was not affected by removing the ECU fuse under the hood. Only the dash one would kill the noise (but not allow it to start either).

 

I have the same issue with my accord. I notice the ECU would flicker as well. Still trying to figure it out.

 

These cars are legendary for a solder connection in the main relay failing causing intermittent/no starts. Search YouTube for "Honda Accord Main Relay" and you can find a lot of information on this.

 

dude just buy a used main relay on ebay, those things are super cheap, stop worrying

 

Check the battery connections are clean and tight.
Verify all grounds/bonding jumpers are clean/tight.
Verify Battery voltage. Fully charged off should be 12,4-12,6.
Verify battery voltage drop when cranking. What is the voltage when cranking? A failing battery may seem 'good' under no load, but under load will show excessive voltage drop. This is also true for faulty/corroded/dirty connections.
Verify the ignition switch is not worn. Move the key up/down/forward/backward when in II(ON) or when in III(Start) if the clicking stops the ignition switch is probably worn.