knightkrawler00

I just finished putting a ZC DOHC in my 1990 CRX DX. I did the wiring myself. It cranks fine, won't fire. Has spark, not sure on fuel pressure, but has fuel getting to the injectors. The injectors are not spraying, not clicking. They ohm tested fine, the resistor box tested fine. With a test light hooked up to the signal wire, it does not flash, just stays on dim, not sure if this is how it should be. The engine will run if add fuel to the intake myself.

The strange part. Whenever the key is turned to on, the main relay buzzes real loud for the two second fuel pump prime. Then continues to buzz when the key is turned to start. If I unplug the Yellow/Black wire from the fuel pump, the buzzing will go away, but no power to the fuel pump wire. If I unplug all of the injectors, the same thing happens, all have to be unplugged.

I have gone over the wiring and can't find where I may have screwed up. I replaced the main relay two weeks ago when it quit on me, so it is brand new. The car ran fine last week when I tore it down, so I know it has to be something with the new parts. I'm running a PG7 ECU that came out of a working car and it has no codes.

Thanks for the help.

knightkrawler00

Somebody's got to have an idea. I've run out of them.

wleach11

Do you have any codes? I had a similar problem with mine and it ended up being the main relay. Where did you get your new relay from? Did you solder the connections or use crimp connectors?

When I had my problem the relay would hold enough for a test light but would fall open when it had to open injectors.

locash

If your main relay is buzzing, check the ground at the thermostat housing and make sure it is connected there from your engine harness.. Also, check the ground from the transmission to the passenger framerail..

knightkrawler00

All grounds are on and tight, it is getting fuel to the injectors. The injectors are not coming on to get fuel into the motor. I don't think I am getting enough voltage on the Yellow/Black wires going from the main relay to the fuel pump and the injector resistor box.

The new relay is from Honda. The connections are crimped at this time, but I checked the voltage drop over the connections, and they are good. I don't have the tools to solder right now. Was planning to get it all together and running, before going back over the harness and finishing it.

What wire comes from the ECU to tell the main relay to energize the fuel pump and resistor box? None of the manuals or information that I have been able to find is really clear on this, maybe I've got a problem in that wire.

knightkrawler00

I got it to run. I grounded the Blue/White wires at the main relay and it runs fine. I think there was a wiring problem with the car before I took it apart and now I aggravated it with the new wiring and ECU. Anybody have any ideas?

knightkrawler00

I think I have it figured out. I grounded the black wire at the main relay and it runs fine. I disconnected the ground at the t-stat housing and I don't have any continuity between the relay and the ground at the housing. Now I've got to figure out where the break in the wire is.

wleach11

Or just run another