question

i had to de pin my plug to get it through my firewall i miss labled two grounds and need to double check.

one is brown with a black strip,the other a black wire
the brown/black wire runs to sensors afm,tps,etc
and the black is an imediate ground can some one tell me which b is b lol

 

https://www.rx7club.com/showthread.p...75#post9235875

 

pm rotarydave2006. he is from the west forum. also, he answered multiple issues with TII wiring---this is in the 1st gen section.

 

k thanks i pmd him



i just dont understand why the br/b wire is labled as b

 

Some wire colors are different on the 87 T2 harness, and some harnesses are labeled differently. The wiring diagram you are looking at is for an 88. I have both year harnesses and I have noticed these differences. The pressure sensor ground wire color is different for example, although it is in the same location on the plug. I think Hailers might have 87 diagrams, at least in hardcopy form that he could scan. I believe all the important pin locations are the same between the two years.

 

your right im using a 86-88 manual from the f.a.q


solved the problem my friend has a hard copy of the 87 fsm

and it turns out 2C isBrB and 2R is B
yay thanks for all help..


who knows where to find the 87 manual online i need to double check all my work,

 

2c and 2R are both spliced together before getting to the plug. Both are one and the same.

Manual and wiring links are in the FAQ on this site OR google ROTORWIKI and the FSMs and wiring are there also. http://www.rotorwiki.com/index.php/Main_Page

Those gnds 2C, 2R, 3A are the grounds for the internals of the ECU and should be made good.

BrB are sensor gnds that terminate in 2C but on later cars the color turns to pure black. You'll see the BrB on the 86-87 cars/FSM's. You'll see pure black on the 88 cars.

First jpg is from the 88 manual. The second jpg from a 87 manual.

 

few questions

i rewired the afm today and noticed i have a brown wire im not sure where to hook it up. The only other brown wire is the temp sender from the ecu. so do these wires merge and go to the sender??

The black/red 3D wire from the em harness says its 12v for fuel pump resistor relay is this a ignition switch wire that turns the pump on and off ? in that case i wire up a relay for my warlbro 255

altitude sensor i noticed i dnt have one in my pile of stuff is this needed for the ecu ?

knock sensor i have read threads that state it dosnt work after 4000rpm and that by the time a real knock sets it off your motor usally toast is this true? can i just discard it when i turbo the engine ill do a tune and wideband etc for saftey.

starter switch. 3B wire do i wire this to the solinoied on the starter?

white/blue 3J wire it wants 12v bat power what kinda fuse should i run on it?

bac valve so i see that this controlls idel or somthing can i do with out it?

i saved the wires for the checker where do i get info on how to make the light box so i can check codes.

i have hooked the primary air bleeds for the fuel injectors up but where the secondarys nipple should be is just a block off plate. do i need to modyfy it and put a nipple on then run it to its spot. or can i get away with no air bleed??

is the sensor on the thermostat housing the temp sender for the ecu?
what sensor goes in to the hole on my water pump housing


heres a pic of my progress of my truck

 

also i dont have a intake sensor can some one show me what it looks like and where it shoulb like in front of the throttle body?

 

3D on a turbo car puts a gnd on the fuel pump/resistor relay assy to change the voltage to the fuel pump from 9vdc to full batt voltage. It's going to be unused on your car. Forget it. You have no fuel pump resistor realy package.

The ECU does not turn the pump on/off. Let's let it go at that. Unused wire pin 3D.

The 3B SHOULD be used. Have it spliced into the trigger wire on the starter solenoid. When you go to START, the ECU needs to see that signal to wake up the ECU's internal fuel map that is used for STARTING the engine. AFM isn't used for Start fuel.

The 3J ......actually the engine will run fine without it.........but on a normal car it's connected to the battery bus via the ROOM fuse (which is in turn powered by the BTN fuse in the engine bay on a series four) so it has power on it 24/7. It's for memory which the series four ECU has little of. I've disconnected the power for that fuse with the car running with no adverse effects at all. But heck, connect it to some fuse that has pwr 24/7. I think the ROOM fuse is 7.5 amps.

The ATP sensor SHOULD be used. Its default value is zero altitude if not connected up. It effects fuel delivery at different altitudes. A car at 8000ft will run rich with it not connected up. I've played with that sensors input to the ECU with a variable resistor to change the mixture. It effects the mixture at all engine speeds unlike the variable resistor that effects idle only. You did install the variable resistor, did you not?

Go google ROTORWIKI for how to download codes from the series four ECU.

There are no secondary air bleeds on a series four engine. Never have been. I've no idea what is blocked off that you sense is a secondary air bleed.

Forget all about the stock knock sensor. Delete all the knock wires/box etc. The deletion has zip effect on the operation of the engine.

Never leave home without your BAC connected up and working. It's just two wires. Do it.

The sensor on top of the water pump housing is for an auxillary electrical fan to sense water temp. If you don't have that aux fan in front of the radiator....ignore it. The water thermo sensor for the ECU is the green plug outfit in the picture. REQUIRED item.

"What sensor goes into the hole on your water pump housing". Thats some previous owners drill job. Not factory. Probably where THEY put a temp sensor for an aftermarket water temp gauge. I find FAULT with that location. I believe that hole is located where the RETURN water from the radiator flows. Makes less than good sense to install a water temp gauge on the return side of the radiator. At least to me. Who cares. Not my car. EDIT: can't help my self. IT a DUMB place to install a water temp sensor. humor

Extra AFM wire????? How about Brown/Black wire??? Say yes. Got two gnd wires from the AFM last time I looked. Spliced together down from the afm plug.......errrrr..if I remember. Actually I just looked and yes, they are both spliced together just downstream of the elect plug on the AFM. BROWN/BLACK wires on early 87.......pure black on later 87 and all 88's.

Something is not quite Kosher with your intake duct/afm etc. I'll let someone else comment on that. I thought this was a turbo engine. I'm confused.

 

Intake temp sensors.........there's two of them. One is internal to the afm and you can see its bulb if you view the vane in the afm. The other intake temp sensor is screwed into the intake elbow AT the engine on a turbo car.

On a non turbo car (series four) it's screwed into the dynamic chamber on the left side.

EDIT: I really don't understand this engine. I know it's in a first gen etc, but is it Turbo or non turbo or/????? hybrid electric? water powered? humor.

 

thank you Hailers.

this is a turbo engine but i am running it n/a and its in a 1974 mazda repu
the reason its n/a is the turbo is worn out.

heres the project hailers https://www.rx7club.com/old-school-other-rotary-63/going-old-skool-got-repu-653888/

3d removed
3b spliced to solinoied
3J ill wire to my new fuse block i wonder if ya can get spade fuses at 7.5
yes the vairble resistor is wired in its next to my pressure sensor in the picture.

looks like ill have to buy a atmospheric sensor will it have to be specific to my ecu n332

"air bleeds" i guess i had the wrong year vac diagram

ill hook the bac up .

looks like ill have to get a new water housing the idiot drilled it right in the center and went through the housing wall lol..

so looks like i need to get a intake sensor for before the throttle body.

ill get back to you on the afm with the list of wires its a brown wire not br/b.


wire 1H where should i be wireing this to i read somewhere that you can hook it to a sensor on the radiator.

 

so i double checked the afm harness and its defiantly just a brown wire if you look at the wire diagram above it show BR on the plug so tell me dose it merge with the water temperature switch wire 1H?? i really have a hard time understanding the schematics of the wire diagram but i have done pretty good so far i think.

 

1H is emissions related on the whole. It was to go to a water temp SWITCH on the bottom of the series four radiator. When the temp in the radiator gets over a certain degree F, the switch MAKES and puts a gnd on pin 1H. Make life simple. Just gnd pin 1H forever somewhere. I assume your not using the series four radiator/emission solenoids.

The hole in the pump housing.........I'd just get a fastener with the right threads and put some RTV on the threads and install that bolt and let it go at that.

Oh. The BROWN wire isn't part of the AFM wiring then. Right? Is it a part of the harness that goes on the engine? The EM harness? Or did you install the FRONT harness on the car also. I'll think on it. Got a jpg of it?

 

Ok. Yes, 1H would just be a brown wire on the EM harness. I'd gnd that wire somewhere. Anywhere would be fine.

Any ATP sensor will do as long as it's series four, turbo or non turbo. Series five don't have 'em (they're internal to the S5 ECU.). Car will start and run without it so don't let that item stall your project out. Just wait til you find one cheap.

The air intake temp sensor for the intake can come from a Turbo or non turbo. Same animal.

 

thanks again

it is part of the afm wireing heres a jpg like you asked


i should have paid more attention where it went to opps..

and i only have the 3 plugs that the ecu needed and rewired everything there is no conection plug to the front harness..

 

Oh. The Brown wire on the AFM plug. It goes to the Circuit Opening Relay on a normal series four car. When the vane in the AFM moves about 1/16 aft, the vane makes a small switch inside the AFM. The contacts of that switch connect that BROWN wire to the BLACK wire on that AFM plug. The BLACK wire goes to two places. One place is on the Yellow, two socket fuel pump check connector and is also spliced into the ECU ground wires that termiate on the top of the engine.

Anyway, that switch puts a gnd on the Circuit Opening Relay to turn on the fuel pump

But you have no FRONT harness and therefore no Circuit Opening Relay.........so that wire serves no purpose at all. And come to think of it the yellow fuel pump check connector also serves no purpose for YOU, for the same reason.

I know not how your fuel pump will turn on. A switch I suppose or off the key/ignition.

The Circuit Opening Relay on a normal series four has two ways of turning the fuel pump on. It has two coils that can make the relay pull in to feed the pump. One way is thru HOLDING the key to START. The other way is once the engine starts and pulls the afm vane aft, that switch in the AFM will pull the Circuit Opening Relay in and keep the pump running once the key has been returned from Start to ON.

I'd just have the fuel pump run off the ignition switch for simplicity. You don't wanna go buy a Circuit Openig Relay and run the wires to it.

 

Yeah, I've muddied the water. The BROWN wire on the AFM plug for YOU does nothing for the reasons I mentioned above (no circuit opening relay for it to go to).

The BROWN wire on pin 1H is not that wire but another wire. That one needs to be grounded. Its in the large plug on the ECU and you have no FRONT harness so ground pin 1H.....somehow. Not critical that you do, but I would.

Confused yet?

 

nope makes sense thanks man your the best ..

 

So. You've got lead and trail coil assy's and are going to or have already run wires from the ECU to them?

And you've got switched power to the fuel injectors from a relay or?????

And you know about what you do if you have low impedence (resistance) fuel injectors vs high impedence fuel injectors. Low are approx 2.1 ohms.......high are ?? 12-14 ohms.

 

yep i ran the ecu wires for the coils.
i have the low impedence resitance box wired in to the injectors and to the main relay fom the second gen which will be trigged by the key.