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-   -   Help on a JDM engine swap (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/help-jdm-engine-swap-434300/)

57bronco 06-15-05 08:31 PM

Help on a JDM engine swap
 
I am helping my 19 year old son swap in a 88 JDM turbo/5spd into a 91 non turbo auto, for insurance reasons. We are getting fire to the plugs and the fuel pump is working, but the injectors are not opening. We used the 88 JDM engine side of the wiring harness and the 88 JDM ECU and even tried the 91 ECU, but, no luck. All grounds and all required wires seem to be intact and connected.

iceblue 06-15-05 09:02 PM

What? Are you sure you have the years right? a 88 is a S4 and a 91 is a S5 both have entierly different ECU's and pinouts and quick connectors to the ECU. This means you rewired the pinouts using S5 connector?

57bronco 06-15-05 09:10 PM

The connectors are the same. I know the 91 is truely a 91, but not exactly sure of the 88 JDM.

Corbit 06-15-05 09:29 PM

look into rotory resurection's site it covers alot of this

bcool 06-15-05 09:34 PM

Since your getting spark the ECU is reconizing that the engine is turning over. Check all connections involving the injectors since you spliced the harness together. Cross reference wiring harnesses from both years in the FSM, see if any of the wires changed color between the year.

57bronco 06-15-05 09:37 PM

I did not splice any wires, the JDM engine harness has the same connectors as the 91. I also used the JDM computer.

iceblue 06-15-05 09:43 PM


Originally Posted by 57bronco
I did not splice any wires, the JDM engine harness has the same connectors as the 91. I also used the JDM computer.

The fule lines on JDM engins are reversed. Did you hook them up right?

Corbit 06-15-05 09:45 PM

The dash harness from the 91 is not the same pin outs as the 88.

Smoken' 06-15-05 09:46 PM

do you have the fuel lines hooked up the right way? On JDM motors, the fuel is routed the oppisite way from what i recall.

bcool 06-15-05 09:46 PM


Originally Posted by iceblue
The fule lines on JDM engins are reversed. Did you hook them up right?

This one has got me before too.

bcool 06-15-05 09:47 PM


Originally Posted by 57bronco
I did not splice any wires, the JDM engine harness has the same connectors as the 91. I also used the JDM computer.

Sorry bout that, must have read it wrong.

57bronco 06-15-05 09:52 PM

Help on a JDM engine swap
 

Originally Posted by Corbit
The dash harness from the 91 is not the same pin outs as the 88.

I am using the 91's original CPU

57bronco 06-15-05 09:57 PM

Help on a JDM engine swap
 

Originally Posted by Smoken'
do you have the fuel lines hooked up the right way? On JDM motors, the fuel is routed the oppisite way from what i recall.

I'll try this tomorrow, thanks for all the input. I'll reply after I try this.
thanks again

iceblue 06-15-05 10:56 PM


Originally Posted by 57bronco
I'll try this tomorrow, thanks for all the input. I'll reply after I try this.
thanks again

If that does it for you :-D

Word of note if it runs now. You can test and start the car on ither ECU. Do not drive it or boost it using the vert ECU. Use the apropriet ECU for the motor. Unless you have spare motors in your back yard.

57bronco 06-16-05 08:28 PM


Originally Posted by 57bronco
I'll try this tomorrow, thanks for all the input. I'll reply after I try this.
thanks again

I swaped the fuel lines and no fuel through the injectors. Any other suggestions?

FB II 06-16-05 08:47 PM

what impedance are the injectors and are you using the correct resistors?

BlaCkPlaGUE 06-16-05 09:53 PM


Originally Posted by FB II
what impedance are the injectors and are you using the correct resistors?

Bingo, its either that or the injectors are junk, wich is pretty damn rare.

iceblue 06-16-05 11:06 PM

Pull the cap off one of the primary injectors. Take a continuity tester to them for ohm and V. Crank the car and see if the harness is even giving a signal to the injectors. If it is not I would say bad harness leads or improper pinout on the ECU for the injectors.

If you are using all S5 components as you have stated. Evrything is high imp then.

You can as well try if you verify the above that the injectors are fireing using a mecanics stephascope and the continuity tester. Take a long flat screw driver and place them on the injectors. With a hammer lightly tap them as they are fireing this will normaly free up stuck injectors. They can tend to become stuck on motors that have ben siting up.

slpin 06-17-05 12:07 AM


Originally Posted by iceblue
If that does it for you :-D

Word of note if it runs now. You can test and start the car on ither ECU. Do not drive it or boost it using the vert ECU. Use the apropriet ECU for the motor. Unless you have spare motors in your back yard.


sadly
you are are wrong...
wait
not sad at all
we expected it
he CAN run SAFELY with the vert ECU

iceblue 06-17-05 12:12 AM


Originally Posted by slpin
sadly
you are are wrong...
wait
not sad at all
we expected it
he CAN run SAFELY with the vert ECU

Sadly you did not learn anything on your last go around with this subject. The only vert ECU that will work is a N338. Now lets revamp a N338 is a S4 ECU and he has a S5 car. :-/

slpin 06-17-05 12:26 AM

yes - but it does not matter
because you CAN run the NA ECU in a turbo car
and it had been done MANY times

you just need common sense... and a brain...

obviously, you dont want to boost 10psi with a NA ecu on 460 injectors
but, there are no problems running the stock 5psi with t2 injectors

Tournapart 06-17-05 12:35 AM

why would you do someting the half ass way if the right way is sitting right next to you? now i would understand if that is all he had was an na ecu but from what ive read he has one na ecu and one turbo ecu.

myexlex 06-17-05 12:50 AM

so let me get this right, he is running the 88 engine harness to an s5 non turbo ecu ? does anyone see a problem in this ?

slpin 06-17-05 12:51 AM

it wont plug in

iceblue 06-17-05 01:04 AM


Originally Posted by myexlex
so let me get this right, he is running the 88 engine harness to an s5 non turbo ecu ? does anyone see a problem in this ?

So it apeard. He has verifyd that it pluged right into his 91 harness and then posted that he was unsure of the year of the TII. Signifying that it must be a S5. What you referd to was my original concern on the project.

// Totaly ignoring the nonsens slpin is posting right now


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