How to make a S4 NA engine harness work with a S4 T2 ECU
#1
Eats, Sleeps, Dreams Rotary
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How to make a S4 NA engine harness work with a S4 T2 ECU
well im turboing my na, i have a S4 t2 engine hanress but its in very bad shape, soo, what would i have to do to make my na hanress work on the T2 ecu and t2 thinngs that need to be hooked, is it even possible???, any details would be Great
thanks
Dustin
thanks
Dustin
#3
Originally Posted by felixwankel88
well im turboing my na, i have a S4 t2 engine hanress but its in very bad shape, soo, what would i have to do to make my na hanress work on the T2 ecu and t2 thinngs that need to be hooked, is it even possible???, any details would be Great
thanks
Dustin
thanks
Dustin
#4
Eats, Sleeps, Dreams Rotary
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do the ECU plugs have to be changed, anyone have a fairly detailed, write up on how to do this, do i really need the knock box, hence my housing dont have a place for the sensor anyways
#6
Just take the blue pill..
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I just recently did a swap to my 87 n/a, and it is very easy, especially if you aren't running emmisions. there weren't any pins to change, and depending on how you route your harness you may have to extend your TPS and BAC a few inches. Everything else plugs right in. You don't need the knock sensor, it will run fine without it. Since you are using your N/a wiring harness you do not have to run any new wires for your temp guage to work correctly. Last but not least, the ECU does not determine the injector resistance, the wiring harness does so it doesn't matter which tII ECU you use. If your car came with low impedance injectors, then for simplicity's sake, use low impedance injectors. Good luck, I am going to go have sex now.....
#7
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Plug and play on the whole.
The only pins that are different are 3D, 2K, 1R.
3D is a ground signal output on a TURBO ECU to the Fuel PUmp REsistor Relay to make the TURBO fuel pump voltage rise/drop. Your non turbo car has no Fuel Pump REsistor Relay so forget this wire all together. ON a non turbo its used on AUTOMATIC transmission cars. So like I say, forget about it.
2K goes to the Split Air solenoid on a non turbo. Its on the ACV. But on a Turbo it goes to the twin scroll solenoid on the engine. You've two things you can do. One is to run the wire from the Split Air solenoid to the Twin Scroll Solenoid on the other side of the engine. Or since you know the twin scroll actuator is spring loaded fully open when there is no vacuum going to its actuator, you could just forget about this pin/wire. Personally, I ran the wire from the split air solenoid to the Twin Scroll Solenoid and it works.
Pin 1R on a non turbo harness goes to a power steering switch. On a turbo it goes to Knock sensor. I ran without a knock sensor for a year or so and then installed a knock box and wired it up. Personally I have no faith the knock box etc is worth a hoot. I'd ignore pin 1R. IF you have power steering I'd depin that wire at 1R. I don't have pwr steering and have an opinion about pwr steering. If I did have pwr steering, I could have made a workaround.
In other words little to nothing has to be done to make it work.
Installing a turbo EMISSIONS harness in a non turbo would be foolish in my opinion. IF you do that, then you have to deal with two other plugs on the emissions harness that in turn connect to the FRONT harness plus you would have to deal with the loss of the alternator plug that is on your na harness but is not on the turbo emissions harness. You'd have to wire in two wires to the alternator plus you'd have to deal with a couple of other wires on the turbo harnes. See connector X-15 or X-16 in your FSM wiring diagram or if you have/had a 88 model they would be called FEM-01 or FEM-02.
You have a 87 series. So just use your non turbo harness and deal with those three pins mentioned above and I'd just forget about the knock box/sensor alltogether.
I have a 87 non turbo car with a turbo engine and a non turbo harness and it runs like a top. IF I had it to do over again, I'd not install the knock box. It seems to me I wasted some effort there. I would make the twin scroll solenoid work like I did. On the other hand others run with it non functional and they can't tell the difference in spool up time. Remember once again, the twin scroll actuator if not connected to a vacuum source, will spring open to it's full open position. So the only side effect is the turbo spooling up a touch slower than normal.
In short, this is the long version of INBROWN'S post just above....and the others.
Yes, the ECU plugs mate up just fine. Be sure to get a TURBO boost sensor. It MATTERS. Plus pickup a TURBO afm to go with it. Using a non turbo pressure sensor is a no/no. Non turbo pressure sensor does not recognize boost pressrue. Not good. Bad. Very bad.
The only pins that are different are 3D, 2K, 1R.
3D is a ground signal output on a TURBO ECU to the Fuel PUmp REsistor Relay to make the TURBO fuel pump voltage rise/drop. Your non turbo car has no Fuel Pump REsistor Relay so forget this wire all together. ON a non turbo its used on AUTOMATIC transmission cars. So like I say, forget about it.
2K goes to the Split Air solenoid on a non turbo. Its on the ACV. But on a Turbo it goes to the twin scroll solenoid on the engine. You've two things you can do. One is to run the wire from the Split Air solenoid to the Twin Scroll Solenoid on the other side of the engine. Or since you know the twin scroll actuator is spring loaded fully open when there is no vacuum going to its actuator, you could just forget about this pin/wire. Personally, I ran the wire from the split air solenoid to the Twin Scroll Solenoid and it works.
Pin 1R on a non turbo harness goes to a power steering switch. On a turbo it goes to Knock sensor. I ran without a knock sensor for a year or so and then installed a knock box and wired it up. Personally I have no faith the knock box etc is worth a hoot. I'd ignore pin 1R. IF you have power steering I'd depin that wire at 1R. I don't have pwr steering and have an opinion about pwr steering. If I did have pwr steering, I could have made a workaround.
In other words little to nothing has to be done to make it work.
Installing a turbo EMISSIONS harness in a non turbo would be foolish in my opinion. IF you do that, then you have to deal with two other plugs on the emissions harness that in turn connect to the FRONT harness plus you would have to deal with the loss of the alternator plug that is on your na harness but is not on the turbo emissions harness. You'd have to wire in two wires to the alternator plus you'd have to deal with a couple of other wires on the turbo harnes. See connector X-15 or X-16 in your FSM wiring diagram or if you have/had a 88 model they would be called FEM-01 or FEM-02.
You have a 87 series. So just use your non turbo harness and deal with those three pins mentioned above and I'd just forget about the knock box/sensor alltogether.
I have a 87 non turbo car with a turbo engine and a non turbo harness and it runs like a top. IF I had it to do over again, I'd not install the knock box. It seems to me I wasted some effort there. I would make the twin scroll solenoid work like I did. On the other hand others run with it non functional and they can't tell the difference in spool up time. Remember once again, the twin scroll actuator if not connected to a vacuum source, will spring open to it's full open position. So the only side effect is the turbo spooling up a touch slower than normal.
In short, this is the long version of INBROWN'S post just above....and the others.
Yes, the ECU plugs mate up just fine. Be sure to get a TURBO boost sensor. It MATTERS. Plus pickup a TURBO afm to go with it. Using a non turbo pressure sensor is a no/no. Non turbo pressure sensor does not recognize boost pressrue. Not good. Bad. Very bad.
Last edited by HAILERS; 12-16-05 at 09:33 PM.
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#8
Eats, Sleeps, Dreams Rotary
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ok, im running a S5 Turbo, so i dont have to worry about that twin scroll thing rite??, BTW thanks HAILERS, your are the man... fyi im have a 88 GXL, with manual steering rack, and im running all stock T2 asccessiories on my NA block..
#10
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so just to make sure, itz all plug and play then, just put the high imp 550s in and hook everything else up and i should be golden?? do i need to cut then 3 unused pins?? or do anything else??..
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i'm a little late on this but, My t2 harness is in bad shape... and from what i understand above you can just use a NA harness and not have to modify anything... Just use t2 boost sensor and ecu? The different pins won't harm anything? Since I have my old s4 block just sitting there with the harness this would be great... just trying to clear things up
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Pin 1R on a non turbo harness goes to a power steering switch. On a turbo it goes to Knock sensor. I ran without a knock sensor for a year or so and then installed a knock box and wired it up. Personally I have no faith the knock box etc is worth a hoot. I'd ignore pin 1R. IF you have power steering I'd depin that wire at 1R. I don't have pwr steering and have an opinion about pwr steering. If I did have pwr steering, I could have made a workaround.
how did i miss this?? i have power steering and couldnt figure out why it kept coming off after a certain amount of time! when i fire the car up i have power steering but as soon as i drive for about 20 minutes i lose it..i never depinned this!! AHHH
so my quiestion is how do i work around this to get my power steering back?
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Originally Posted by 88rxn/a
well ill be a damn!!!
how did i miss this?? i have power steering and couldnt figure out why it kept coming off after a certain amount of time! when i fire the car up i have power steering but as soon as i drive for about 20 minutes i lose it..i never depinned this!! AHHH
so my quiestion is how do i work around this to get my power steering back?
how did i miss this?? i have power steering and couldnt figure out why it kept coming off after a certain amount of time! when i fire the car up i have power steering but as soon as i drive for about 20 minutes i lose it..i never depinned this!! AHHH
so my quiestion is how do i work around this to get my power steering back?
#17
tom port.. AKA streetport
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i see, so it could be the relay inside the PS unit then? i read the FSM and found the power steering stuff but i got lost and really didnt comprehend it. is there a way to check to see if the unit is good VIA mulltimeter?
#18
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You'll get nothing but blank looks from me about power steering. I have none. But it seems to me the electrical part of the steering on a series four is insignificant. It seems if you turn the wheel the switch makes and puts a gnd on a pin in the ECU that then makes the Air Supply Valve open which in turn makes the engine speed go up to compensate for the load put on the engine by the pwr steering pump.
The pwr steering section in the fsm seems to have you check the power steering pump pressure out plus check for the right oil level in the pwr steering reservoir.
I suggest someone with pwr steering pipe in and give suggestions. Or you could make another seperate thread that asks about pwr steering?? YEs.
The pwr steering section in the fsm seems to have you check the power steering pump pressure out plus check for the right oil level in the pwr steering reservoir.
I suggest someone with pwr steering pipe in and give suggestions. Or you could make another seperate thread that asks about pwr steering?? YEs.
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i was readin about the 2k wire if you use a turbo harness do you still run the wire over? and do you just tap in a wire and run it to the twin scrolls or do yo cut it free of the split air solenoid and run it to the twin scolls
#20
Originally Posted by HAILERS
You'll get nothing but blank looks from me about power steering. I have none. But it seems to me the electrical part of the steering on a series four is insignificant. It seems if you turn the wheel the switch makes and puts a gnd on a pin in the ECU that then makes the Air Supply Valve open which in turn makes the engine speed go up to compensate for the load put on the engine by the pwr steering pump.
The pwr steering section in the fsm seems to have you check the power steering pump pressure out plus check for the right oil level in the pwr steering reservoir.
I suggest someone with pwr steering pipe in and give suggestions. Or you could make another seperate thread that asks about pwr steering?? YEs.
The pwr steering section in the fsm seems to have you check the power steering pump pressure out plus check for the right oil level in the pwr steering reservoir.
I suggest someone with pwr steering pipe in and give suggestions. Or you could make another seperate thread that asks about pwr steering?? YEs.
I'm at work so I can't check the FSM. Can anyone tell me if 1R is an output or input to the ECU?
I would think a rogue input signal for knock wouldn't exactly be a good thing.
If it's output to PS then it's less of a worry.
#21
Why is not having the knock sensor ok ?
I thought the knock sensor was made to help save the engine by advancing timing under knock ?
I would look into turboing my n/a but i think its more worth it to just buy a turbo 2 so i can have both na and turbo , although turbo na does sound very tempting, Id just rather have a better drivetrain if i was running on a tII and would probably need a ems to run any boost higher than about 12psi
I thought the knock sensor was made to help save the engine by advancing timing under knock ?
I would look into turboing my n/a but i think its more worth it to just buy a turbo 2 so i can have both na and turbo , although turbo na does sound very tempting, Id just rather have a better drivetrain if i was running on a tII and would probably need a ems to run any boost higher than about 12psi
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wow - i cant believe i missed this thread!!!
isnt the power steering speed sensitive? i think i can recall someone mentioning that and if so, with the lack of a ground signal to the air supply valve wouldnt that affect the ps as it did with 88rxna?
Originally Posted by HAILERS
You'll get nothing but blank looks from me about power steering. I have none. But it seems to me the electrical part of the steering on a series four is insignificant. It seems if you turn the wheel the switch makes and puts a gnd on a pin in the ECU that then makes the Air Supply Valve open which in turn makes the engine speed go up to compensate for the load put on the engine by the pwr steering pump.
The pwr steering section in the fsm seems to have you check the power steering pump pressure out plus check for the right oil level in the pwr steering reservoir.
I suggest someone with pwr steering pipe in and give suggestions. Or you could make another seperate thread that asks about pwr steering?? YEs.
The pwr steering section in the fsm seems to have you check the power steering pump pressure out plus check for the right oil level in the pwr steering reservoir.
I suggest someone with pwr steering pipe in and give suggestions. Or you could make another seperate thread that asks about pwr steering?? YEs.
#23
I used a TII Harness for my swap. and I never touched the 1R pin. I'm now building a NA harness for a TII swap for a person and am wondering about what 1R really does.
It may be unrealted but I have noticed my steering is touchy at random times. SO maybe the PS is getting signal or somethign through this and turning on when it shoudl be off at higher speeds? again. It could be completely unrelated.
It may be unrealted but I have noticed my steering is touchy at random times. SO maybe the PS is getting signal or somethign through this and turning on when it shoudl be off at higher speeds? again. It could be completely unrelated.
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a long block is the whole engine intake manifold, dynamic chamber, water pump, ETC. basically what you get when you pull an engine straight out of your car . a short block on the other hand is just the block 3 irons , 2 housings , 2 rotors, and an e shaft . there are however some variations on this but that is what it means basically