1992 Honda Civic DX 4dr
06-29-2009, 07:56 PM
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Re: 1992 Honda Civic DX 4dr
If you try another ECU, you will be able to see if it makes the fuel pump prime or not. You don't have to worry about trying to start the engine.
Grab the ECU pinout diagram, grab a multimeter, and check to see if the fuel pump enable wire goes low when the pump primes and then back to 12V.
If you look at the relay schematic eric posted, the relay coil gets power from the battery, and the other side of the coil is wired to the ECU. Because there is no current flowing in the wire until the ECU enables that output, there will be 12V on that wire. The ECU switches that wire to ground to turn on the relay, so that wire will then go low (to zero volts) when the relay is on.
Therefore, if there isn't 12V on that wire at any time, the ECU is fine and the problem is upstream somewhere. This is what troubleshooting is all about; see what you have, see what you need, figure out what those differences are.
If the car is a 92, it's old enough that you may have a wire broken from fatigue or a loose fuel pump ground or something like that.
You can pull the proper fuses and check to see if there is power at the fuse contacts too. If the fuse isn't getting power, it doesn't matter if the fuse is good or not.
Grab the ECU pinout diagram, grab a multimeter, and check to see if the fuel pump enable wire goes low when the pump primes and then back to 12V.
If you look at the relay schematic eric posted, the relay coil gets power from the battery, and the other side of the coil is wired to the ECU. Because there is no current flowing in the wire until the ECU enables that output, there will be 12V on that wire. The ECU switches that wire to ground to turn on the relay, so that wire will then go low (to zero volts) when the relay is on.
Therefore, if there isn't 12V on that wire at any time, the ECU is fine and the problem is upstream somewhere. This is what troubleshooting is all about; see what you have, see what you need, figure out what those differences are.
If the car is a 92, it's old enough that you may have a wire broken from fatigue or a loose fuel pump ground or something like that.
You can pull the proper fuses and check to see if there is power at the fuse contacts too. If the fuse isn't getting power, it doesn't matter if the fuse is good or not.
Last edited by Fabrik8; 06-29-2009 at 08:12 PM.
06-29-2009, 08:38 PM
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Re: 1992 Honda Civic DX 4dr
Ok that MPI fuel pump relay i will have to check this week, I have a b16 obd1 ecu, is it safe then to try & see if maybe the ecu currently in the '92 4dr sohc is the problem? The last few posts have been a big eye opener thats for sure be sure to check into that when i get the time from work, as the car is still sitting at my job lol.
Thanks fellas keep an eye on this & as soon as i check these things mentioned i'll be back in touch.
I do know that all the wiring at the fuel pump assembly itself was double checked & was stated they were all fine 'looking' & connected properly as they are suppose to be.
relay(s) are my next task, along with the ecu swap.
Thanks fellas keep an eye on this & as soon as i check these things mentioned i'll be back in touch.
I do know that all the wiring at the fuel pump assembly itself was double checked & was stated they were all fine 'looking' & connected properly as they are suppose to be.
relay(s) are my next task, along with the ecu swap.
06-30-2009, 06:11 AM
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Re: 1992 Honda Civic DX 4dr
You can use the B16 ECU to see if the fuel pump primes, yes. You'll throw knock sensor codes and it won't really run that great, but like I said before you don't have to start the engine to see if the fuel pump primes.
07-05-2009, 06:01 AM
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Re: 1992 Honda Civic DX 4dr
Haven't had much time to check the car out. A buddy needed a fuel injector to borrow for a few days (actually just the orings) I ordered new ones due to the fact mine were practically shot. So theres one more thing down thats fixed. Just wish it would start & run so i could sell this thing lol. But its soo clean it makes it hard.
10-05-2009, 09:32 PM
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Re: 1992 Honda Civic DX 4dr
What would cause the front end alignment (which has been fixed 2 times by bennets here in f'burg, very well known for lowered vehicles).. They have done the alignment twice. & its horrible now. Pulls to the left steering wheel is cocked 1/4 turn to the right just to keep the car straight now...
10-06-2009, 03:25 PM
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Re: 1992 Honda Civic DX 4dr
What would cause the front end alignment (which has been fixed 2 times by bennets here in f'burg, very well known for lowered vehicles).. They have done the alignment twice. & its horrible now. Pulls to the left steering wheel is cocked 1/4 turn to the right just to keep the car straight now...
10-06-2009, 04:10 PM
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Re: 1992 Honda Civic DX 4dr
I do believe tire pressure is correct 13in steelies.. I'll look into the rack next chance i get.. I know the trust towers are slightly cracked on top but having tein full coilover suspension im not sure why they are cracking like they are..