9 replies to this topic

[Speedcult]

So I need a little help here. The 87 Si is almost finished, problem is no fuel to the rail. Can't hear the pump so I use my PowerProbe and give it 12 volts. PLENTY of fuel to the rail then. It worked before I tore it apart in August and I never touched the back of the car. Is there a relay or something I missed. I've been working in a freezing garage (22 degrees) and no heat except coffee and hot chocolate (thanks wifey). On top of that, the #4 injector leaks when I juice the fuel pump. Between work and working on this in the cold, I'm a little tired. Any help guys as to what I missed? I'm off tomorrow and will try anything you guys suggest and let you know the results.

[DEIVIONCRX]

So you supplyed 12volts directly to the pump and it ran?

If thats so, id check the main relay(drivers side under the dash by the hood release) as they are the typical problem with hondas, then check the ECU for the signal to turn the pump on.

[Speedcult]

Yeah I gave the pump 12 volts and I get fuel to the rail.

I was looking for the relay, I have 2 boxes that look like main relays just above the fuse panel... one actually IS on top, the other looks like it's mounted on the firewall at an angle. The one on top of the fuse panel is loose... not bolted or clipped down, just laying up there ????WTF????

Someone must have been in there before. I also noticed that the injectors are NOT firing either. No gas is getting IN the engine. When I spray a bit of starting fluid it starts right up and then dies unless I spray more. So I know it's a fuel problem. That relay controls the injectors as well?

As soon as I know which box is the relay, I'll test it. This happened to my 91 CRX too when I did my ZC swap in the snow LOL!

[DEIVIONCRX]

It doesnt control the injectors directly, but it does turn the ECU on which inturn runs the injectors.

[Speedcult]

Tested the relay as per the guide and got continuity and heard the relay open and close. So next up a faulty ecu? Like I said, everything else is fine. Strong spark, runs great off of starting fluid, no CEL on.... just no pump power or injector pulse. Grrrr... damn injector o-rings were old and brittle.

Is the computer in the hatch the same as the 88-91's? Passenger footwell? Does it have the same diagnostic "window"? Sorry, my youngest daughter is falling asleep on me so I can't check it just yet.

[DEIVIONCRX]

It is under the Passanger Front Seat, It does have the Diagnostic Window but it doesnt blink the codes like the 88-91's There is 4 LEDs and depending on which are lit up thats the code.

[Dennsco]

Well I inherited the 87 civic si from speedcult and will pick up this thread were he left off, I have looked over everything and cannot find any obvious reasons as to why it still wont run. Its does seem that its not getting fuel into the cylinders, the fuel pump is working when it is jumped with power. I rechecked the fuel relay, and its operating, I replaced the ECU with a good working unit and still nothing. This one has me stumped, any Ideas?

[DEIVIONCRX]

Check all of your wiring, from the battery to the relay, relay to ecu, relay to pump, pump to ground, ect..

[Dennsco]

After a number of hours troubleshooting the electrical problems and testing relays I eventually found I had a bad ground wire to the ECU.I tried tracing its anchor point back through the harness, believe the manual indicates it attaches to the engine block under the hood but could not find its termination point so I spliced in a new ground lug and she is purring like a kitten! I really ...really hate electrical gremlins! Thanks for your suggestions Deivioncrx!

Edited by Dennsco, 31 December 2007 - 10:36 AM.

[DEIVIONCRX]

The ECU ground is at the Thermostate housing.