Main relay?
Thread Starter
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Joined: May 2002
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From: Tampa
Main relay?
Hey guys...this is more documentation for future searches than anything.
Intermittent problem here that seems to be permanent now. Basically, the civic won't start (starter goes, but the engine never fires, fuel pump doesn't kick on). When I turn the key to on, everything comes on as it should, but the CEL, Airbag etc. lights don't. The main relay doesn't click either. The alarm is in Valet mode also, so that shouldn't be it. I'm assuming its just the Main Relay and am gonna rip it apart tonight....
Intermittent problem here that seems to be permanent now. Basically, the civic won't start (starter goes, but the engine never fires, fuel pump doesn't kick on). When I turn the key to on, everything comes on as it should, but the CEL, Airbag etc. lights don't. The main relay doesn't click either. The alarm is in Valet mode also, so that shouldn't be it. I'm assuming its just the Main Relay and am gonna rip it apart tonight....
Thread Starter
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Joined: May 2002
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From: Tampa
v-card member alpha
Joined: Oct 2006
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From: Assplosion, NE
Just fyi, I've read that a bad main/fuel relay on at least some civics will allow the fuel pump to prime but the injectors don't get power.
The end result is the same, no start, but just b/c someone hears the pump prime might not necessarily mean their relay is working.
You could either crank it and pull a plug to see if you smell fuel, or if you've cranked it enough you'll get fuel running out the intake. I wouldn't suggest doing that on purpose but when my coil died it happened, just glad I use upper cylinder lube (plus a lot of oil was getting by the valve seals back then, lucky timing.)
In your case since you don't get the prime, it still could be the relay for all I know, maybe the bad, cracked solder joints on yours happen to affect the pump or maybe your year's main relay functions more like most Hondas :dunno: otherwise the problem could be elsewhere. I was leaning towards the relay shortly before my coil died but if you used to hear a click from the relay and now don't I think you're on the right track. Good luck
The end result is the same, no start, but just b/c someone hears the pump prime might not necessarily mean their relay is working.
You could either crank it and pull a plug to see if you smell fuel, or if you've cranked it enough you'll get fuel running out the intake. I wouldn't suggest doing that on purpose but when my coil died it happened, just glad I use upper cylinder lube (plus a lot of oil was getting by the valve seals back then, lucky timing.)
In your case since you don't get the prime, it still could be the relay for all I know, maybe the bad, cracked solder joints on yours happen to affect the pump or maybe your year's main relay functions more like most Hondas :dunno: otherwise the problem could be elsewhere. I was leaning towards the relay shortly before my coil died but if you used to hear a click from the relay and now don't I think you're on the right track. Good luck
Senior Member
Joined: Apr 2003
Posts: 6,157
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From: Dallas, TX
Sounds like it is most likely your main relay. When mine went out, my fuel pump didn't prime either. I didn't have time to solder mine when it went out so I just bought a new one.
It does sound weird that your CEL isn't lighting up at all. Mine still lit up and went out like normal (I just didn't hear the fuel pump). I hope it isn't your computer.
It does sound weird that your CEL isn't lighting up at all. Mine still lit up and went out like normal (I just didn't hear the fuel pump). I hope it isn't your computer.
Thread Starter
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Joined: May 2002
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From: Tampa
Ok, it isn't the relay. I re-soldered it, then even bought another. I pulled out the multi-meter and checked the harness....I'm getting 12v where I should, but nothing comes through when I turn the key. Time to make sure the alarm isn't causing the issue. I'll bypass that wire and go from there.
