s4Lt

OK so, from the s4 or s5 thread I've gathered I had an s5 engine.

Now everything is done except I'm having fuel plug issues with the ECU.
This is the ECU that came with the engine and wiring harness:



Now, the plugs from "Picture 2" fit inside the ECU in "Picture 3":


But the plug for the fuel "Picture 1" (from what I'm told) doesn't fit into the ECU I got shown in "Picture 3":


Now, what am I supost to do?
Is there another ECU I can get that will manage just this plug or is the only way is to do some rewiring?

Thanks!

s4Lt

So I did some reading on the rotaryresurrection.com website and found out that the Junction plugs under the kick panel wouldn't fit into the new turbo ecu and the engine harness. So now I would like to know what people have done to overcome this? Did you scrap the plugs and just direct connect the wires? My dash/main wiring harness is from an s4 and the engine is an s5. If I can't direct wire everything then is there a place I can buy an s5 dash/main wiring harness to replace my s4 one? I know that at this point I should have just bought a turbo rx7 but I was hoping that the shop I bought the engine from would have sent me the s4 to make life easier and I've already put too much money to just scrap the swap. I'm very frustrated at this point, any help with this would be greatly appreciated.

lnlycrpr

the third plug you need is the dash/main harness plug. have you tried to see if it fits? if so, then you should be fine. not sure what the plug in pic1 is, but i doubt it has anything to do with fuel. the plugs in pic2 are what will controll the engine/fuel.

driftedfc3s

S4 and S5 electronics and wiring don't match up. You will either need to get S4 electronics, wiring, etc or go stand-alone.

s4Lt

what stand alone will work with this? I keep contacting people but they never get back to me. What specifics standalones should I be getting?

HAILERS

A standalone won't run the electric OMP and you get to rewire the engine bay to boot.

There are a couple of choices. Get a series four TURBO ECU and use your old n'/a harness on the engine. This still means the electric omp won't work and you have to do the silly premix with the gas.

Or do the step above but also buy a series four turboii front cover WITH the mechanical omp on it and swap that out to the S5 engine. There's still a problem because the lever that operates the mechanical omp needs to be connected to the throttle body and there's no fitting on a series five throttle body for such. So that has to be overcome.

If your real keen on using the series five ECU, you could get both series four and five wiring schematics and go to town depinning wires from plugs and mating them up with the correct other wires . Probably not an option for you. It might be interesting to match a series five EM harness to a series four Front harness. It'd be time consuming, but doable. I've only seen ONE post where this was done and it was a friend of HIGGI's that did it. Forgot his name. Started with a $ sigh I think. Czech Republic fellow. But to follow what he wrote required some past knowledge of the harness/ECU's.

Or install a series five Front harness in your car. Not a reasonable thing to do in my opinion. Personally I'd match the Series five EM harness up to the series four Front harness before I'd screw myself like that.

And if that is a JSPEC EM harness in the picture, that is even worse. It would be for a right hand drive car and would have no wires for the wiper motor. So you'd have to install wiring b/t the wiper motor to the series four front harness for the wipers to work.

So this rambling got your thread back to the top of the page.

HAILERS

The series five and four FSm's both have a page called CONTROL UNIT. It's in the fuel section. There you WILL find what each and every pin on the ECU does in life. In other words what that large plugs wires do in life.

HAILERS

The attached jps show what the pins in the series five ECU do in life. It's in the FSM also.

s4Lt

hummm, I'm going to have to read that a couple times over cuz it flew right over my head. I'm a noob at this stuff. I don't really care what ecu I use as long as it works. The engine is imported from Japan and it is right hand drive. I just bought another s5 turbo ecu cuz I though they sent me the wrong one but the pins from both are the same **sigh**, is there a way to get those pictures bigger and more clear? What book/manual it come in so I can grab it and give it to my mechanic to get this stuff done. The engine I got is a complete kit, everything came with it and he still has my s4NA engine. But as far is this goes the only issue is the plugs from 2 different series that don't plug into each other there isn't any after market wire harness adapters for this kinda thing is there? But ill start with re-reading what you wrote first and see what I can understand =)

HAILERS

https://www.rx7club.com/forum/showthread.php?t=494667

Manuals and links

s4Lt

Ok so I just talked to my mechanic and he said that when he turns the key the engine wants to start. If he puts fuel in the injectors the car will start for 5 seconds.
So everything is working fine but the injectors aren't shooting any fuel. He said that there is missing an ECU to control the injectors for that big plug you see in "Picture 1". So he has his electrition looking into his Japan "connection" lol to find me a parts number for this missing ecu, but lets say they cant find it. Can I simply just put an after market one to control only the fuel system? Would that make it shoot fuel at the right times and such? and if so which one would I need to get to make this work? Thanks allot for the help.

jgrts20

So lemme get this straight you have a S5 engine in a S4 body and you using the S4 harness, right? In my book technically you should have the S5 engine harness. Im not sure but maybe if im correct you might be able to run the S5 engine harness along with the S4 dash harness. If its a JSPEC......................um I think your screwed, you will have to make your own harness for the car(doing the pin thing like Hailers was explaining). Goodluck!!

s4Lt

Yeah I have a Japan s5 motor (with the s5 harness), in a s4 body(with the s4 harness).
The car will run, the only thing stopping it from starting is the fuel injectors aren't shooting any gas cuz there isn't anything telling them to. The engine gets spark but isn't getting any fuel to get the explosions to get the car running. So what I'm saying is that I need something to control the injectors, to tell them "hey, shoot this much fuel now". So is there an stand-alone injector computer or something that will control the fuel system and still us the factory s5 ecu? I don't know if its cuz I can't explain this properly or not, the only thing I need is for my injectors to start shooting fuel into the engine and then the car will live, so if there is a stand-alone control system that will do the injector controlling please let me know which one it is. The engine wants to start but isn't getting the fuel from injectors.

I hope I explained it in enough different ways that someone will understand one of them lol.

jgrts20

Maybe you should buy the JSPEC wire harness!! If you can find one, I think to run standalone you need the injectors to be running on theyre own.

s4Lt

Thats all I need is the injectors to work, if they work i have a working car lol.
all I need is something that will control the injectors only, make them squirt fuel into engine so there can be a boom.