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-   -   Late 10ae vs early 10ae (injectors/electrical)?? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/late-10ae-vs-early-10ae-injectors-electrical-990860/)

flipside27 03-11-12 10:04 PM

Late 10ae vs early 10ae (injectors/electrical)??
 
so ive come to the problem with my 10AE where everything is pretty much stock with the exception of the injectors and harness.

After getting the spare engine rebuilt/replaced, I also swapped my original harness with the one that came with the engine.

Later discovering that the two were completely different.
The original had purple plugs/injectors.
The current has red plugs/injectors.

Everything else dealing with my engine is fine. perfect compression, no leaks internal or external, everything has been tested 100 times over...literally.

but the car still smokes due to a fuel leak into the engine somewhere.
Could it possibly be
  1. The ECU is sending the wrong signals because of the wrong harness/injectors?
  2. The injectors are just bad?
  3. The fuel pump is bad?

anyone experience these issues?

FirstRotaryExp 03-11-12 10:08 PM

Are the injector connectors round/oval or square/rectangular? If the connectors are round/oval its an S5 engine/injectors, if square/rectangular its an S4 engine/injectors then it breaks down into where the offset is on the injectors, there is a difference between where the keyed offset is (centered vs offset to the side) but I cant for the life of me remember which is a high impedence injector and which is low.

flipside27 03-11-12 10:18 PM

The Red injectors/clips which are currently on the vehicle are square with the offset notch. The PURPLE ones that came with the car originally are square center notch.

and thanks for the quick response

flipside27 03-11-12 10:28 PM


Originally Posted by RETed (Post 5672522)
Just the clarify...

The low-impedence 1986 - 1987.5 FC turbo fuel injectors are *purple* brand new.
When faded, they look gray / tan.

The high-impedence 1987.5 - 1988 FC turbo fuel injectors are *red* brand new.
When faded, they look pink.

Both sets use the rectangular "Bosch-type" plug, but the keys are offset due to the difference impedences.

The low-impedence, early year ones are center keyed.
The high-impedence, later year ones are offset to the side.


-Ted

Found this in another thread. can anyone verify if this is accurate?
Also would this matter to the ECU if the harness and injectors were the paired properly?

FirstRotaryExp 03-11-12 11:44 PM

Ted's correct.
The ecu doesnt care what injectors you have (high or low) as it will try to read the high impedance values, however if your car or current harness has the injector resistor box, you need to be using the low impedence injectors, or else you will burn up something trying to use high impedance injectors with the resistor box.

Personally I wouldnt have changed the harness/injectors unless the old harness was in bad enough shape to need replacing (it was known good vs the 'new' harness that was in unverified condition same with the injectors). Whenever ive done an engine swap, i never reused any wiring harness that came with the engine, nor the injectors and oftentimes nor the intake. Why change parts you knew were working a certain way (possibly happily together) and then introduce 'new' parts of unknown condition..

As for the very original question, its possible the 'new' injectors you are using are sticking open. A faulty fuel pump wont dump more fuel into the engine, it will either work or not flow enough and eventually stop working. Id look to see if the injectors are sticking, and also look to see if the pressure regulator is working properly (as in not allowing more pressure than it should or see if its leaking fuel back into the intake itself throught he vac line.)

flipside27 03-12-12 01:29 AM

Thanks so much man.
And at the time I did the swaP I knew very little about anything. And your right that was a very poor decision. But here I am 2 years in.

So I guess the next step I should take is simply getting new injectors to guarantee that it's working proper. Second ill check the FPR And see if it's proper.

Again, thank u for your time and I'll keep u posted.

FirstRotaryExp 03-12-12 11:21 AM

No problem, I was about the same way with my first swap. I spent 2 hours trying to figure out why I wasnt getting fuel, and the answer was that I had reversed the fuel lines due to mazda changing the emissions hardlines routing between 87 and 88, but I knew enough to use my old injectors and harness on the 'older' block.

Though im about im a similar boat with my honda since nothing from the old motor transferred onto the new one, aside from the new injectors sitting on my tool chest that have yet to make it into the car.

j9fd3s 03-12-12 12:45 PM

just for the clarification, the 10AE is a 1988 model, so it would have had the high impedance injectors and no resistor box harness originally.

FirstRotaryExp 03-12-12 03:38 PM

That may be, however OP clearly stated that his original injectors were purple, which were according to re-ted low impedence. Its very likely the car could have been a good clone or that someone else aside from OP did some changes and did not do them correctly.

misterstyx69 03-12-12 03:53 PM

Is there a resistor pack on the harness?..that would mean LO impedance injectors.


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