EGI Pump Relay Clicking, Ignition coil clicking & No start

[jdm_dean]

Im having some weird problems. I have a 90 hatch with a SOHC. It was recently swapped, had a blown ka24de. Swapped over to a ka24e, ran fine then all of a sudden issues out of no where. The EGI Pump Relay clicks rapidly whenever the key is engaged. i know that controls the fuel pump and the fuel pump is working fine

cars getting plenty gas because the plugs come out smelling like fresh gas. Compression is good, but im not getting any spark other than cylinder 1. switched ignition coils & transistors, same issue. new wires & plugs, dizzy cap & rotor. same issue. im stumped...

[rioredstang]

Relays clicking usually mean bad grounds or low voltage. I would guess a bad ground.

[jdm_dean]

i was thinking the same thing. ive checked every ground possible and still cant find anything loose or missing. :\

[jdm_dean]

bumpp

[shiro_neko]

checking ground zerothread/159907

adding grounds zerothread/216236

[jdm_dean]

just tried that. resistance between ground and battery negative was good. :\

[sx moneypit]

Have you tried unplugging the ECU to see what happens?

[jdm_dean]

Yeah, tried that numerous times. No effect on the situation

[shiro_neko]

pull out your ecu. connect your DC voltmeter (-) to ground. probe your (+) to these terminals while ecu harness is connected:

34 - start signal. 8-12v when cranking.

36 - ignition switch. 0v when "OFF". battery voltage when "ON"

104 - fuel pump relay. battery voltage within 5 secs after turning to "ON"



did you check the resistor? re-check your ignition coil & transistor

[jdm_dean]

At work but ill try that tommorow.

[jdm_dean]

edit below.

[jdm_dean]

So yeah

basically..

starter signal good
ignition switch good
fuel pump relay, 3 volts max, wasnt battery voltage.

but when i unplug the egi pump relay and measure the two pins on the right i have full battery power.

but the relay just wont stay connected, even switched relays, same deal.

so thinking maybe theres a short between the ecu pin 104 and the relay??
and with the key in the ignition i hear the fuel pump priming, but it wont stop after 3 seconds it just keeps going, so im guessing the relay has the pump confused, turning on and off???

[shiro_neko]

Yeah better check that wire. its supposed to be battery voltage. this is what supplies current to your fuel pump relay to keep it open. also check the black wire with white stripe in your fuel pump relay. its goes to your fuel pump fuse

[jdm_dean]

Thanks man. With the sohc ecu in the ignition voltage was good, starter signal was good but the fuel pump relay would vary from 2v to 12. Put in a dohc ecu and the car did like you said. Pin 104 was .8 v for exactly 3 seconds then exactly battery voltage steadily without the relay clicking.

So that let me know that it wasn't a wiring issue. Also when id try and put the sohc ecu in diagnostic mode the ecu never blinked. Dohc does though. So basically it was my ecu. It was fried so it wouldn't ground the fuel pump relay steadily. Thanks for the help. Hoping someone sees this thread and it helps them.

[shiro_neko]

thats good to hear