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Discussion Starter · #101 ·
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If you are still using the jumpers on the main relay the engine light probably wont come come on, now that key is working have you checked to see if the main relay operates normally?
There should be battery voltage to the injectors when key is on, but they shouldn't be getting hot, so something strange is going on. Double check the injector impedance, if those somehow ended up being obd0 injectors and you are running obd1 harness and ecu with no resistor box that could be the cause of the heat in both ecu and injectors.
Is there a way to tell what injectors they are? Markings/number/style etc?
 

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Discussion Starter · #102 ·
If you are still using the jumpers on the main relay the engine light probably wont come come on, now that key is working have you checked to see if the main relay operates normally?
There should be battery voltage to the injectors when key is on, but they shouldn't be getting hot, so something strange is going on. Double check the injector impedance, if those somehow ended up being obd0 injectors and you are running obd1 harness and ecu with no resistor box that could be the cause of the heat in both ecu and injectors.
I did have the main relay plugged in and im not jumping the relay. How do you check injecyor impedence? With a volt meter?
 

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93 4d lx, z6,ported, port matched, compression bumped, balanced, manual swap
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Yes a digital volt-ohm meter is what you will want to use, select the lowest or auto range on ohms and test across the injector pins, if its below 14.4 ohms(i think, id have to look it up) thats likely where your heat is coming from.
 

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Discussion Starter · #104 ·
Yes a digital volt-ohm meter is what you will want to use, select the lowest or auto range on ohms and test across the injector pins, if its below 14.4 ohms(i think, id have to look it up) thats likely where your heat is coming from.
All the injectors tested at 12.4. We also pulled the injectors out and they all spray fine but it's just a constant spray.
 

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At cranking speeds you should be getting tiny squirts, not full time spray, injectors are the right impedance, but you must have some wiring problem, time to start tracing wires from ecu through the jumper harness and cabin harness and to the fender connectors I think, something is shorted in there, or wires got crossed somehow, not surprising with the shape the wiring was in when you got it. Start with resistance checks between injector connectors and their corosponding ecu pins, check that when unplugged from ecu and injector that they have to path to ground.
 

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No, you have high impedance injectors and an obd1 ecu, are the injector circuts being pulsed? I'd rent a noid light set to be sure, it could be stuck open injectors , but that wouldnt explain the heat in the injectors or ecu, sounds more like a wiring issue to me, some short or crossed wires.
 

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Discussion Starter · #110 ·
No, you have high impedance injectors and an obd1 ecu, are the injector circuts being pulsed? I'd rent a noid light set to be sure, it could be stuck open injectors , but that wouldnt explain the heat in the injectors or ecu, sounds more like a wiring issue to me, some short or crossed wires.
Okay, just trying to look at every angle possible. I got the whole harness off the car again and will start going through every wire and trace it back to the where it goes. When reading the ecu plug from the wire side. You count top to bottom correct? Not going across?
A1 A3
A2 A4
 

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Obd0 ecu pinout, you will need to make sure your conversion harness matches it to
The obd1 pins
 

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Grab a multimeter and find out the actual resistance of your fuel injectors. 12-16 is the optimal range. The lower the resistance, the more power they are drawing form the ecu, and that is why low impediance injectors will kill your ecu in a heart beat.

From the ecu pinout diagrams you will find above, make sure all your harness grounds are connected and being used.
 
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Then it is possible the circuits inside the ecu are fried and shorted out, staying activated. The ecu merely provides a ground to activate the injectors. They have 12v at all times when the key is on.
 

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Discussion Starter · #115 ·
Update: anyone got a p06 or any other ecu that would run it for sale?? Pretty sure the one I have is toast. I've traced every wire and nothing was bad or out of the ordinary
 

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Didn't you have a pm6? I think you tried it before but not since you got the main relay issue sorted.
 

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Has the cabin harness been converted, or just a jumper harness? it should start it, won't run well but it should fire up and stumble around idle, would at least verify that it is indeed the ecu.
 

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Discussion Starter · #119 ·
Has the cabin harness been converted, or just a jumper harness? it should start it, won't run well but it should fire up and stumble around idle, would at least verify that it is indeed the ecu.
I got a complete engine and cabin harness from a 94 dx from my work (i manage a recycle yard) the only thing not wired up is the wire to the fuel pump. When I put power to that wire that goes to the pump (coming from the relay) it just sprays constantly. It does start with the key, it will run ( we haven't ran it for very long because we don't have the coolant system hooked up yet) but with just the key on the injectors will heat up and be hot to the touch.
 

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Only the ecu controls the firing of the injectors. The injectors are always "hot" with 12v, but should be ONLY activated via a grounding at the ecu.

If the injectors are constantly spraying, the ecu is indeed dead or in need of repair.


I have an auto P06 that works. You can convert it to manual with a piece of wire and a soldering gun easy enough, though I do like the usage of a 0-ohm resistor to act as a fuse of sorts.

PM me. I would likely do $20 plus shipping. I would need a couple days notice.
 
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