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Here is a partial pic of the wiring diagram B-! (Engine Control system) for Version 1 JDM. You can compare to the USDM diagram.
I observe the following: The EGI relay gets power through the circuit from the EGI fuse. The egi relay also gets a signal from pin 1K of the ecu The egi relay also gets power from the ignition through the "engine" fuse in the Joint Box.
The 20A fuel pump fuse gets power directly from the ignition and then feeds power to the fuel pump relay, through the "circuit opening relay".
The circuit from the 1k pin (ecu) runs through the Fuel Pump relay connecting to the EGI main relay.
There is also a device called the fuel pump register that seems to run parrallel to the fuel pump relay.
I don't know what all that means. That is why we simply disconnected the fuel pump at the top of the gas tank, when we were doing the deflood.
You might want to check if the 1K pin of the ecu is bent, or otherwise damaged.
Here is a partial pic of the wiring diagram B-! (Engine Control system) for Version 1 JDM. You can compare to the USDM diagram.
I observe the following: The EGI relay gets power through the circuit from the EGI fuse. The egi relay also gets a signal from pin 1K of the ecu The egi relay also gets power from the ignition through the "engine" fuse in the Joint Box.
The 20A fuel pump fuse gets power directly from the ignition and then feeds power to the fuel pump relay, through the "circuit opening relay".
The circuit from the 1k pin (ecu) runs through the Fuel Pump relay connecting to the EGI main relay.
There is also a device called the fuel pump register that seems to run parrallel to the fuel pump relay.
I don't know what all that means. That is why we simply disconnected the fuel pump at the top of the gas tank, when we were doing the deflood.
You might want to check if the 1K pin of the ecu is bent, or otherwise damaged.
that’s really helpful info,
the egi fuse in the engine bay looks fine (not blown) and I’ve checked the engine fuse under the dash and it’s fine and replaced it with a new one too just in case.
the fuel pump fuses and main circuit relay should be fine considering fuel pump does run as per the video when I set the key to on and fuel came out of the supply.
I think the smartest thing to do is to take out a spark plug after cranking it tomorrow to see if it’s wet right after a crank. That way we can confirm if the injectors are at least spraying. I have spark so if the plugs are wet after a crank, that means the old gasoline is the issue. It also helps to know if I use starting fluid it runs on that.
if plugs aren’t wet then I doubt the gasoline is the issue, then for some reason the injectors aren’t firing but it honest to god doesn’t make sense why not. Car worked perfectly fine before and all I did was replace OEM stuff with OEM stuff besides the wiring harness that I got from wiring specialties (it’s made to be like the OEM harness). I connected everything correctly too connector wise and didn’t do guesswork.
about the 1k pin to the ecu, I wonder if that’s one of the pins that is part of the engine harness? If so, then it can’t be that because I put a brand new engine harness from wiring specialties in.
what else would prevent injectors from firing? Bad ground? Only grounds I remember off the top of my head are the one to the side of the upper intake manifold that connects to firewall and then the one the engine harness has that connects to the block itself.
man I really want this car running, just on OEM parts I’ve spend close to $4k on maintenance maybe more.
Was going to suggest listening for the primaries clicking.....with a makeshift stethoscope if need be if you could reach.
All my wiring diagrams are on a recalcitrant hard drive and long time since last playing in the area, but if the EGI was bad, I would have thought the pump would've been a problem all along too, but that's based on pulling the EGI fuse rather than the relay. That relay *** fuse fuse box clips in, you should be able to turn it upside down and probe the backside of the relay in situ with ign on and off. If you replaced the CAS wiring, it suggests the emissions harness was pretty toasty, and disturbing it to replace fuel lines might have had an adverse effect too.
Wouldn't like to chance the radio relay if they're 100 bucks , buckleys being the same current capacity, the thermoswitch wouldn't be a problem.
ok so this guy mentioned using a stethoscope to see if injectors are clicking. I’m sure I can go buy an actual stethoscope but reaching the primaries with the UIM and everything on might be impossible. Reaching the secondaries is easy but don’t think they come on during startup. I can try to leave the stethoscope under the UIM and see if I hear any clicking through it though? Might be something else though it could pick up
How much of your rats nest is gone? If it is a lot, then if you remove the triangle vacuum chamber in front of you UIM, you might be able to get at the injectors.
That vacuum chamber may also be gone.
(Sorry to say, but harness makers sometimes screw up. They were aware your car is JDM, right?)
1k connects directly to one of the Front harness plugs (B1-01) and the wire blue/white runs through the Front Harness directly to the fuel pump relay.
Yes it seems your fuel pump seems to be working,.
My showing the diagram was to demonstrate that pulling certain fuses/relays might not cut power to the fuel pump.
Therefore, pulling the EGI relay to do the defllod, might not in fact stop the fuel pump from pumping.
It seems the "fuel pump register" , whatever that is, bypasses the fuel pump relay.
(It seems the circuit opening relay beside the yellow egi relay, is more relavant.)
How much of your rats nest is gone? If it is a lot, then if you remove the triangle vacuum chamber in front of you UIM, you might be able to get at the injectors.
That vacuum chamber may also be gone.
(Sorry to say, but harness makers sometimes screw up. They were aware your car is JDM, right?)
1k connects directly to one of the Front harness plugs (B1-01) and the wire blue/white runs through the Front Harness directly to the fuel pump relay.
Yes it seems your fuel pump seems to be working,.
My showing the diagram was to demonstrate that pulling certain fuses/relays might not cut power to the fuel pump.
Therefore, pulling the EGI relay to do the defllod, might not in fact stop the fuel pump from pumping.
It seems the "fuel pump register" , whatever that is, bypasses the fuel pump relay.
(It seems the circuit opening relay beside the yellow egi relay, is more relavant.)
yeah I thought wiring specialties messed up so I called them today and they assured me they didn’t. They said their harnesses are computer tested yadda yadda—hopefully it’s true.
also to your other question yes I keep my battery fully charged.
my car is LHD Usdm and I ordered a USDM manual harness from them.
my front vaccum chamber is off yes. It’s connected via vac lines but it’s not bolted down so I can peek under the UIM from there
The 1k is part of the biggest plug that goes into the ecu right? I have a diagram for it attached to confirm it’s what you’re talking about. I’m assuming it’s not damaged because if it was the pump wouldn’t run?
I only have the 1994 USDM wiring diagrams. They look much different from the Version 1 JDM diagram, althoough the circuits look soemwhat the same. USDM Version 1 (1993) and Version 2 (1994) may have differences. In the 1994 USDM the 1K seems to be connected fuel pump relay.
I am not certain, but that connection may be to tell the ecu the fuel pump is running, rather than the ecu telling the fuel pump to run.
I am curious why your gasoline appears to be green.
this gas is from July 28th to be exact. I also use idemetisu premix but that’s about it. I might have to go buy some brand new gas and mix it with that premix and see if it makes that color but I don’t know what color to expect. I wonder if I ever put engine dye in there when I was looking at fuel leaks. Will have to look through receipts for that.
Ok also although I’ve had to rip apart my whole top to change the CAS sensors over and over again, I think I might have to again.
just thought about it, maybe the CAS sensors are dirty? (Not the connectors). Like oil covering them which is preventing injectors from firing? Tomorrow I will first crank and check spark plugs for fuel, if there is no fuel I will take apart the whole thing to access CAS sensors and attempt to clean them. What should I use to clean the sensors? Electrical cleaner? Thanks
Let me also add that I sent my injectors to injectorrx for cleaning before I installed them. They sat for about a month before I put them in the car and attempted to crank. Do you guys think maybe they got stuck from sitting after being cleaned and flow tested?
Do you still have the old harness? Would it be worth temporarily swapping back to the old one and see if you still have a no start, just to rule out the new one or not?
what else would prevent injectors from firing? Bad ground? Only grounds I remember off the top of my head are the one to the side of the upper intake manifold that connects to firewall and then the one the engine harness has that connects to the block itself.
The good book - wiring - should have a page or two dedicated to the earthing points. One I've missed in the past is a chassis ground up the LHS in the vicinity of the PS pump. ECU controls injector firing via earth switching. Noid lights should tell you if the injectors are getting signal, might tell if there's been a mix of a 850 secondary for the primary, but I'd want to hear or see the firing. If the injectors have been cleaned a month ago, short of being imbeciles like some of the wheel alignment places over there, I'd hope you'd be good, UIM loose with a nice long screwdriver to your ear on the primary rail, if you can reach it, should be sufficient for a stethoscope.
I pulled the trailing plug closest to firewall, cleaned it, stuck it back in and cranked and pulled it out and no gasoline on it.
injectors aren’t firing.
now my next steps are to take off the UIM, and do a click test on the injectors to see if they’re stuck. No clicking means stuck right? I will also get a noid light and attach it to the connector to see if ecu is firing (which I think it is because ecu shows injection percentages).
Billyboy, the place I sent my injectors to were injectorrx, they seem reputable no? Well I hope so.
outside of stuck injectors or the noid light possibly not working, what else could be the issue? Besides those two possible culprits, I’m fresh out of ideas guys
I am thinking that Yellow premium gas plus blue premix makes green. But that is just a guess.
(Is diesel green in Arizona?)
I just got my rails and injectors back and they are gong in tonight. Refurb cost C$570 mostly labour as I supplied the seals, FPR and FPD (another C$500).
Shop kept the rails an extra day so to leave in the ultrasound cleaning machine longer. Inside of rails was highly corroded.
I just found that the wiring diagrams can be found at page F-213 of the USDM FSM (Factory Service Manual). - Mine is the 1994 "final" issue).
I am thinking that Yellow premium gas plus blue premix makes green. But that is just a guess.
(Is diesel green in Arizona?)
I just got my rails and injectors back and they are gong in tonight. Refurb cost C$570 mostly labour as I supplied the seals, FPR and FPD (another C$500).
Shop kept the rails an extra day so to leave in the ultrasound cleaning machine longer. Inside of rails was highly corroded.
I just found that the wiring diagrams can be found at page F-213 of the USDM FSM (Factory Service Manual). - Mine is the 1994 "final" issue).
I haven’t changed the gas yet and don’t think I will because I now know the injectors aren’t even firing. It might run with the gas in it right now.
Check 1k yet? If the ECU does not know the pump is running , it might not fire the injectors.
it seems injectors are fed power from the Main Relay through the front harness and then the emission harness (sometimes miss-called engine harness) through connector x-05.
Each injector is connected separately to the ecu at pins 4W, 4Y, 4X and 4Z. through connector B1-01.
I have seen where the front harness is damaged where it passes through the fire wall, perhaps from someone jamming after market equipment wires through the same hole.
The EM harness could be damaged in the same way.
I assume your replacement harness replaced the EM (emissions harness).
12-19-23, 11:01 PM
, buckleys being the same current capacity, the thermoswitch wouldn't be a problem.
