RotaryResurrection

iTrader: (8)

LOL, how about you go back and read my wiring answer again.

People want to know why nobody wants to give them free advice and answers and instead they get told to search. This is why...you do it and you still get questioned. I told you what part wouldn't work and why, and yet here you are anyway.

I have a jspec longblock that some guy bought and installed and found out that 1) the harness is missing a plug and it won't work properly and 2) the engine was blown anyway. If I think about it, I will take pics of that harness for comparison to a US spec harness. Youll see that one of the big plugs near the ecu is missing altogether, and a lot of wiring with it. I dont know why this isn't simple to understand...missing wiring on the harness = not fully functional.

As for the ecu, the car should start and run with the turbo ecu and a nonturbo harness/engine, however it may not run smoothly. The turbo ecu has a shorter idle injector pulsewidth due to the turbo's larger injectors, so it may run the NA a little lean and make it want to stall...or it may be okay. Never tried it that way...I have run turbo engines on NA ecu's with no real issues at all.

2RotorSpeed

iTrader: (1)

OK, like I said, your answer confused me because I've been getting so many different answers from people that I just didnt know what to believe, so I'm sorry, and don't take that as any offence. I gave up my intention of using the Jspec harness, and I will try to make the N/A harness work instead, since people say I only have to rewire the knock sensor. No, I can not afford the Aspec T2 harness like you reccomend, tho if I had the money I would do so. And thanks for the answer on the ECU question. Now I think I have all my answers for the swap, and I can start PRAYING that my engine doesnt come with low compression (No, I also dont have the money to send it to get rebuilt right now, unless it comes with low compression, then I will not have a car to drive for few months, maybe until next summer, lol).

Dak

Took me awhile but here is what I could dechipher from my FSM. This is from my 1989 workshop manual from Mazda.
Differences are as follows:
Pin# 2M on N/A = VDI Control soleniod
Pin# 2M on TII = Knock Sensor.
So I would guess the wire that went to the VDI Solenoid gets connected or extended to connect to the knock sensor.

Pin# 3R on N/A = 6-port induction system(solenoid)
Pin# 3R on TII = Duty solenoid valve(Turbo boost pressure control) From the turbocharger control system section it looks like this is the solenoid that controls the wastegate valve actuator. I would guess same as above for wiring.

Pin# 1U on N/A = AT switch
Pin# 1U on TII = Mileage sensor #2 Don't know what to do about this one.

Pin# 3N on N/A = EC-AT Control(This is an output)
Pin# 3N on TII and MT N/A has no connection.

I would reccomend comparing the FSM pages yourself as well to make sure I haven't overlooked something. Also I'm pretty sure this will not apply to 87-88 cars. Applies to 89-91 cars only.

HAILERS

The above is why going using a n/a harness on a turbo motor really works well on a Series Five car, or even putting the turbo EM harness on the n/a car.

On a series FOUR car things are a bit different. Not so much the wires on the engine to the ECU but the problem on Series Four is the plugs on the EM harness that mate with the FRONT harness. There is the real problem with putting a turbo EM harness on a Non turbo. The wires at the plugs that mate with the FRONT harness are uncomfortably different b/t turbo and non turbo.

So on a series four, it is easier to leave a non turbo EM harness in the car and attach it to the turbo engine. Then make small changes on a couple of wires on the engine, similar to what DAK wrote above for the series five.

On a series five engine, the plugs that mate the EM harness to the F harness are X-10, X-11, X12 and SEEM to be the same for turbo and non turbo. No so on a series FOUR though (different plug numbers also on S4).

2RotorSpeed

iTrader: (1)

Alright, thanks a bunch. I think the 2M and 3R should be relatively easy to take care of, I probably dont have to worry about 3N since my 89 was always a MT. And 1U... well my quesion is, what am I losing without the 1U connection after the swap? My odometer? lol

HAILERS

I read page F2-78 (Control Unit) and see that once the car has over 600 miles, the milage switch in the cluster puts a ground on pin 1U to let the ECU know that the car has over 600 miles on it (engine has over 600 miles).

Looking at page F2-74 we see the RELATIONSHIP CHART for the number two milage switch. We take note that it has an effect on: Lead and Trail timing, Duty Solenoid Valve and Fuel Injection Amount.

I'd put a gnd on that wire (pin 1U). You can do whatever you wish to do.

The S5 FSM is available for a free download. Download the FUEL section.

EDIT: Well, just forget I wrote the above. There seems to be a Large discrepancy b/t the free online series five wiring diagrams and the ECU pinouts in the manual. The wiring diagram on page C-2, shows the milage switch going to the boost sensor output wiring which is patently wrong. I suspect that wiring diagram isn't right but the pinout is right. I'd still put a gnd on 1U. Maybe someone can figure out where I went wrong when looking at page C-2.

Dak

Looking in the wiring section of my manual it says "miles sensor no.2 in the combination meters. In the control system section it shows it is in the instrument cluster as well. It also says below 600mi approx. 12 volts. Over 600mi. below 2v. So it may be ok to ground it. I would almost just leave it unconnected or floating.Since all N/As are missing this then anyone who has done a conversion even when using the TII harness is missing this part and most likely it is left unconnected. I also meant to say in my last post that all other pins on the ECU except those I mentioned are identical.

2RotorSpeed

iTrader: (1)

I downloaded the online manual from this following thread:
https://www.rx7club.com/forum/showthread.php?t=530860

Hope I got the right manual haha.

Anyways:
N/A - Pin 1U - Input - AT switch - To EC-AT Control Unit (#28 on page H-1) - Goes to EC-AT Control Unit Pin 2N? - Condition(Always Grounded)
Turbo - Pin 1U - Input - Milege sensor #2 - To Instrument cluster (#32 on page C-2) - Goes to Volt Gauge? -

Btw, this is the first time in my life trying to read one of these books, lol, so please keep in mind if you see me making 100 mistake =D.

Few qeustions:
What's AT switch? or what it stands for?
What's the EC-AT (Control Unit) stand for, and what's it for?
Let me take a wild guess, the two above questions are about automatic transmission as stated above? So should I really have to worry about it? And it seems the 1U pin on the Turbo models goes to the volt guage...

Let me know if I'm reading this right... hehe, thanks.

2RotorSpeed

iTrader: (1)

I also don't see where the N/A knock sensor plugs into the harness. If the trubo ECU has a pin 2M for the knock sensor, shouldnt the N/A have a pin for that as well? Just a bit confused.

HAILERS

********- To Instrument cluster (#32 on page C-2) - Goes to Volt Gauge? - *********

Theres's something wrong with that. I mean, look at the page C-2 and it shows the number two milage switch and it does not go to 1U. If you follow the wires from the number two milage switch you find those wires are related to the boost sensor.

So I think they are no showing the boost gauge in C-2 but are mislabeling it as the mileage sensor.

I'm going to find a manual for series five to look at or go to AllData.com and look at their schematic. I don't trust that online manual for right now. Not anymore. Well, at least not page C-2.

HAILERS

2M on a non turbo ECU goes to the VDI solenoid.

2M on a turbo goes to the knock sensor.

The turbo engine has no VDI solenoid so you'd just run the wire that exists for the VDI solenoid to the knock sensor on the turbo engine. That's if you used a non turbo harness on the turbo engine.

Both items are located in the same area on the engine so it shouldn't be a big deal/hassle.

2RotorSpeed

iTrader: (1)

So the N/A engine does not have a knock sensor? But the Turbo engine should come with one? If so, where is the knock sensor located on the T2?

P.S. I havnt bought my T2 engine yet, I have everything for a full swap including drivetrain but not the engine, I am about to in a few weeks tho =)

2RotorSpeed

iTrader: (1)

Wait, so I'm assuming you have to pay for AllData.com in order to see their manual for you car? =(

HAILERS

On a series four the knock sensor is screwed into the intermediate housing on the left side of the intermediate housing. On a S5 it's located .....errrrr........ahhhh.....on one of the rotor housings???? I guess I coulda looked at the s5 FSM . It's on the left side of the engine for sure. A one wire sensor.

If you have a S5 car, then use your present n/a harness. Like NZConvertible said, it'll plug in just fine and start up. Just some mild changes should be made, like connecting to the knock sensor and putting the VDI elect plug on the boost solenoid.

And yes, ALLDATA.com requires a fee. I'm not sure I'm even a current subscriber, but I think I downloaded the schematics to my laptop.

HAILERS

Yeah, I just looked at the diagrams I downloaded from ALLDATA sometime ago. Pin 1U is a BR/R wire that goes to Milage Sensor Number Two on the cluster. NOT as shown in the online series five diagrams.

So like I said, just ground pin 1U because your engine has more than 600 miles on it and that is what happens with the original car when it hit over 600 miles.

2RotorSpeed

iTrader: (1)

Thanks for further research.

Alright, don't worry I will be using the n/a harness for this swap. I'll take care of knock sensor by splicing it into the VDI plug, and use the 6PI plug for the duty solenoid, and run a ground for pin 1U... when I find it =)

Hope that's as far as my electrical problems will be.

And I have to make sure the I dont get the fuel lines backwords on the fuel rail since its a JDM engine.

Oh, and whats a recommended way to start the engine, which probably hasnt started in God knows how long... I'm talking about making sure the engine is lubricated when you first start to crank it?

HAILERS

You could pull the sparkplugs out and spin the engine. That way it has no load on it plus it will spin faster. The oil pressure should rise on the gauge when you do that.

Or you can do that and something else. Like pull the oil filter off. Then with a squirt can, squirt oil into each of the two holes in the pedestal. One hole leads to the engine and the other to the oil cooler/lines.

Maybe pull the elect plug off the CAS when you do the above so no fuel is injected during the spin over (don't want to wash the housings down with fuel).

2RotorSpeed

iTrader: (1)

Are you supposed to take out all 4 spark plugs out?

And as for the fuel pump I've had it individually wired from the battery to always get full voltage for years, so I can just pull out the fuse I have for it to stop the fuel pump from running.