Main relay location on 87 civic?
bzee
09-05-2002, 01:42 AM
My '87 Civi Si quit on us today (thank goodness it was at home). It'll crank over and start, but die within a couple of seconds; subsequent cranks will only turn over the engine.
Doing some research on the web, I've reached the conclusion that it's the Main relay that's bad. After cooling down, I can hear the fuel pump running when the key is turned, and the PGM-FI light is on. If I hear the pump running, the car will start if I turn the key all the way. After it dies, I won't hear the pump anymore when I turn the key, and the car won't start.
Anyhow, I've crawled all under the dash of the car, and tried searching the net for hints, but I can't find the location of the main relay!! I've seen pictures of what the relay should look like, it has 7 wires going to it, and that it's most likely on the drivers side high in the dash. However, I can't find it.
Can someone with a service manual look it up please?
Thanks,
BZ
Doing some research on the web, I've reached the conclusion that it's the Main relay that's bad. After cooling down, I can hear the fuel pump running when the key is turned, and the PGM-FI light is on. If I hear the pump running, the car will start if I turn the key all the way. After it dies, I won't hear the pump anymore when I turn the key, and the car won't start.
Anyhow, I've crawled all under the dash of the car, and tried searching the net for hints, but I can't find the location of the main relay!! I've seen pictures of what the relay should look like, it has 7 wires going to it, and that it's most likely on the drivers side high in the dash. However, I can't find it.
Can someone with a service manual look it up please?
Thanks,
BZ
Miguel Gonzales
05-18-2003, 09:47 PM
Well i had the same problem as you..I thought....After i ripped everything apart and bought a new relay and ecu. Turns out a plug to the ecu got disconnected. Dumby me. Well at least i got the car running again. Boy was i ticked off and happy at the same time. Put it this way i didnt tell my wife. hehe The answer to your question is. Its behind the fuse panel. First remove the plastic fuse cover. Then theirs two 10mm nuts holding the fuse panel. After those are removed you'll have access to the relay. its bolted to a steal panel on the side. 2o'clock from the hood release. You can unscrew the relay with a short phillips or remove the steel panel if you cant reach. its being held on with a 10mm nut. You want the relay thats marked Mistuba RZ-0042 12v or main relay..duh!
The cost from the dealer is $53.00 and took a week. I have 1 extras if you need. But I would check the relay first and the ecu connectors.. dumby me.. I guess i learned from my mistake..well you just did. Any repair manual with show you how to test the relay. Glad to help..
The cost from the dealer is $53.00 and took a week. I have 1 extras if you need. But I would check the relay first and the ecu connectors.. dumby me.. I guess i learned from my mistake..well you just did. Any repair manual with show you how to test the relay. Glad to help..
spdracr87
05-25-2003, 01:39 AM
did u check yoru fuel line to c if its gunked up that happens alot withthose lill lines if u dont put cleaners in tehm offten. and it whould do tha same things u saying it is
spdracr87
05-29-2003, 10:35 PM
i bet thats y mine is stuttering. that or from the guy i bought it from just replaced timeing belt maybe it aint on bye a noch any one know about that one.
Miguel Gonzales
05-29-2003, 11:42 PM
If it was the relay it wouldnt start. Sounds like your timing is off. Should check it. That or your injectors are clogged. Should have them cleaned. If you need any parts let me know.
spdracr87
05-30-2003, 05:36 PM
k thanks man. that what i was think that my timeing belt was off. and was going to clean injectors any ways.
spdracr87
06-08-2003, 01:56 PM
ok my father was looking at soem things on line and found out that soem of it could be my o2 sencer on my header. u all ever here any thing about that
johnboy27
06-11-2003, 09:50 PM
Originally posted by bzee
My '87 Civi Si quit on us today (thank goodness it was at home). It'll crank over and start, but die within a couple of seconds; subsequent cranks will only turn over the engine.
Doing some research on the web, I've reached the conclusion that it's the Main relay that's bad. After cooling down, I can hear the fuel pump running when the key is turned, and the PGM-FI light is on. If I hear the pump running, the car will start if I turn the key all the way. After it dies, I won't hear the pump anymore when I turn the key, and the car won't start.
Anyhow, I've crawled all under the dash of the car, and tried searching the net for hints, but I can't find the location of the main relay!! I've seen pictures of what the relay should look like, it has 7 wires going to it, and that it's most likely on the drivers side high in the dash. However, I can't find it.
Can someone with a service manual look it up please?
Thanks,
BZ
Do you know how to solder or know anybody who works with electronics alot and could do it for you.If you do,then you could have them check the cold solder joints inside of the relay.That is what goes wrong with these relays and if you know how to fix them then there is no reason to replace them.See if somebody could fix it for you and give it a try.
You could go to the junk yard and see if they will let you try out a used one just to make sure it is your problem.
My '87 Civi Si quit on us today (thank goodness it was at home). It'll crank over and start, but die within a couple of seconds; subsequent cranks will only turn over the engine.
Doing some research on the web, I've reached the conclusion that it's the Main relay that's bad. After cooling down, I can hear the fuel pump running when the key is turned, and the PGM-FI light is on. If I hear the pump running, the car will start if I turn the key all the way. After it dies, I won't hear the pump anymore when I turn the key, and the car won't start.
Anyhow, I've crawled all under the dash of the car, and tried searching the net for hints, but I can't find the location of the main relay!! I've seen pictures of what the relay should look like, it has 7 wires going to it, and that it's most likely on the drivers side high in the dash. However, I can't find it.
Can someone with a service manual look it up please?
Thanks,
BZ
Do you know how to solder or know anybody who works with electronics alot and could do it for you.If you do,then you could have them check the cold solder joints inside of the relay.That is what goes wrong with these relays and if you know how to fix them then there is no reason to replace them.See if somebody could fix it for you and give it a try.
You could go to the junk yard and see if they will let you try out a used one just to make sure it is your problem.
rusted
07-18-2003, 10:25 PM
I've been all over a 91 CRX looking for its main/fuel relay as well. I felt above/behind the fuse panel but no joy.
Is it really up there? I'm not looking forward to pulling it out.....
Is it really up there? I'm not looking forward to pulling it out.....
johnboy27
07-18-2003, 10:55 PM
In the 88-91 civic/crx the main relay is located right above the hood release behind the kickpanel.Unbolt the hood latch and remove all the connectors that keep the panel on down there and then look above(I believe) where the hood release would be.You should see a black box that is bolted on there with a ten mm bolt.That is the main relay.
rusted
07-19-2003, 12:30 PM
Johnboy suggested it is on the side of the 91 CRX.. Well I pulled the hood release and looked behind the carpet, etc.
No joy. There's 2-3 lines (fuel/vapor?) and a cable bundle that run down and back along the inside of the door sill, but no relay.
I also disconnected a buncha connectors and pulled the fuse panel down; on its back is flat 2x3" module that I think is the beepbeepbeeper but no relay. No yellow wires visible either.
The dealer sez the Fine Manual claims it to be along the outer wall but I sure do not see it anywhere...
The car has a VIN of JHMED8354M... is it really a Yugo in disguise, perhaps?
No joy. There's 2-3 lines (fuel/vapor?) and a cable bundle that run down and back along the inside of the door sill, but no relay.
I also disconnected a buncha connectors and pulled the fuse panel down; on its back is flat 2x3" module that I think is the beepbeepbeeper but no relay. No yellow wires visible either.
The dealer sez the Fine Manual claims it to be along the outer wall but I sure do not see it anywhere...
The car has a VIN of JHMED8354M... is it really a Yugo in disguise, perhaps?
rusted
07-19-2003, 03:10 PM
I found the &*^*^& thing...
It's on the sidewall but inside the dashboard. (Hiuh?)
When you open the door, some of the dashboard sticks out rear of the door frame itself. (The top of this plastic is where the heater vent that blows onto the side window is..) Between two layers of plastic, to the rear and above the hood release, there sits...
If, as I did, you pull the little flip open coin tray, you can see the top.
I resoldered all the joints in it and the car started, so maybe that will do the trick.
Since I was on a roll, I jacked it up, pulled the LF wheel and got the alternator bolt off with an impact wrench. But to snake the alternator out the wheelwell, you first need to pull the alternator bracket off the block. Then it's easy....
I'm off to find an alternator that does NOT whine like a bad date.
It's on the sidewall but inside the dashboard. (Hiuh?)
When you open the door, some of the dashboard sticks out rear of the door frame itself. (The top of this plastic is where the heater vent that blows onto the side window is..) Between two layers of plastic, to the rear and above the hood release, there sits...
If, as I did, you pull the little flip open coin tray, you can see the top.
I resoldered all the joints in it and the car started, so maybe that will do the trick.
Since I was on a roll, I jacked it up, pulled the LF wheel and got the alternator bolt off with an impact wrench. But to snake the alternator out the wheelwell, you first need to pull the alternator bracket off the block. Then it's easy....
I'm off to find an alternator that does NOT whine like a bad date.
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