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ImmaculateNatas
11-30-2019, 02:43 PM
I have an S13 Hatch SOHC original car. I've swapped a DOHC motor in. I've used the FSM and know all the grounds are correct and are clean for best ground possible. My car has also been swapped with a digital crackless dash before I bought it.

I've also replaced all fuses and relays with brand new ones. New distributor, ignition coil, plugs, and wires. I've also done the ignition coil mod.

The ECU to dash plugs are obviously different so I've spliced/soldered/shrink wrapped them in what I believe are the correct wires;

ECU Plug black wire - Grounded to engine (also tried body)
Dash Black - Data, not using
Blue/Black stripes - Water Temp
Yellow/ Red Stripe - Tach Signal
Yellow/ Green stripe - Speedo
Orange - ignition

I have every color from the dash plug to the ecu plug matched up other than the two blacks as previously stated.

So when I first started to fire up my car I didn't hear the fuel pump prime. At first I assumed it was just a bad wire somewhere in the harness and correctly hooked it up to a toggle switch, which gave me fuel pressure and it is making it to the rail.

Now I've realized I'm not getting spark and fuel isn't going into the cylinders either so the injectors aren't firing. I know my timing is correct as well.

So I figured out my ECU isn't working. Borrowed one out of my friends running car and the ecu still isn't working.

Sorry for the wall of text but I just wanted to give as much information as possible before asking for advice!

Any advice on how to move forward?

OnTheChip
12-01-2019, 10:22 AM
You will need a KA24DE ECU as the CAS timing is 30° retarded from the single cam CAS and ECU.

ImmaculateNatas
12-01-2019, 10:31 AM
I should have put in my post that I do have a KA24DE ECU. When I bought the car, I bought it as a rolling shell since the car was in immaculate condition. Nothing in it is from a SOHC anymore.

S14rebuild
12-01-2019, 01:11 PM
Fsm...check power and grounds to the computer...its not turning on

kyral
12-01-2019, 02:01 PM
Eccs relay not turning on will cause you to not have fuel or spark. why its not turning on is gonna be the big question.
check your ecu to see if you red led is lighting up. the ecu grounds the eccs relay to turn it on, if the ecu doesn't turn on the eccs relay wont pop off and you wont have fuel or spark

ImmaculateNatas
12-01-2019, 02:29 PM
The red light is not turning on which is why I've narrowed it down to the ecu not getting power. I've tried both KA24DE ecus I have and neither light is turning on so I know it's not a faulty LED. I'll look into the eccs relay.

kyral
12-02-2019, 12:52 PM
if that's the case its power to the ecu that's the problem, the ecu turns the eccs relay on when it itself turns on. so the problem may lie in the ignition switch or wiring to the ignition switch,

Its a black red wire to the ECU pin 36 that turns the ecu on
theres a white wire at the ignition switch that should have 12v at all times, if not blown fuse or broken wire. then once the ignition switch is ON the black red wire should also have 12v of power that it feeds to the ecu to turn it on.

super easy to test check 12v at white wire ignition off or on doesn't matter
then check for 12 at the black red wire on the switch, ignition in run position
if all is well check for 12v at pin 36 on the ecu also a B/R wire.
youre problem is going to be somewhere around there

(wire may be slightly different color if you have a SOHC car 89-90)

reference chapter EF&EC page 90 in FSM

ImmaculateNatas
12-02-2019, 02:54 PM
Thank you so much for the detailed advice! I'll check it all out whenever I have free time again!

ImmaculateNatas
12-07-2019, 06:47 PM
Kryal, thank you so much! My car is now starting and idling! Had to make a toggle switch harness and hook up to the 36 pin. Once my ECU got power everything worked as it should. Can't thank you enough man!