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S15 SR20DET no injector pulse

Posted: Sat Nov 03, 2018 10:46 am
by Scott Black
Recently had a nistune board installed in an ecu for an s15 I have at my shop.
Car came in running using his mates ecu (car with same injectors and afm as his) and he left me his ecu (or so i thought at the time)
Got the board installed, adjusted to suit the afm and injectors, car wouldn't start, No injector pulse
Tried putting the entire bin file from the ecu he drove the car to me on in the new ecu, and still no start.
No Injector Pulse
Called customer and found out the ecu he supplied wasn't the original from the car, and his car never came with an ecu when he got it.
Its a JDM S15 SR20DET
The working ecu that belongs to his mates car is part number 23710-91F05
The ecu he left me part number is 23710-91F01
I Have no injector pulse with his ecu, I have power at the engines, and I get no injector pulse output from the ecu (verified with scope)

What Im trying to work out now is are the ecus compatable or are they the ADM/JDM NATS / ECU pinout stuff around
The car does have spark.
The nistune board itself is communicating fine and can read and right, I can view the gauge page and see cranking rpm, load and everything else I normally see.


Re: S15 SR20DET no injector pulse

Posted: Mon Nov 05, 2018 9:38 am
by Matt
So vehicle is S15 JDM SR20DET, and both ECUs you have listed below are S15 JDM SR20DET (91Fxx) so there is no mismatch there

Can you confirm you get the fuel pump prime for several seconds on key on? You are also seeing a few hundred RPM on the gauges when cranking?

If not then check bar code on side matches the A18 number on the main ECU sticker

Details on ADM/JDM here:

Are you getting any fault codes at all?

So the vehicle was running on the ECU before you installed the Nistune board? Try uninstalling the board and put the ECU jumper back to factory mode to see if it starts and runs. Also reconfirm it runs with the second ECU still. Something strange going on

So you are checking injector pulse width a test light?

Re: S15 SR20DET no injector pulse

Posted: Mon Nov 05, 2018 9:47 am
by Scott Black
It shows 200 rpm exactly when cranking
Fuel pump primes
ill check for fault codes shortly
Has spark
Testing for pulse with both a scope and a noid light
Checked for power at injectors with multimeter
Car has never run with this ecu.
Ill try to confirm it still runs with older ecu as soon as i can as i need to have the owner bring it back down to the shop


Re: S15 SR20DET no injector pulse

Posted: Mon Nov 05, 2018 3:25 pm
by Scott Black
Got the other ecu back,
Put it in same issue.
traced it back to an aftermarket alarm playing up so now all fixed

Re: S15 SR20DET no injector pulse

Posted: Wed Nov 07, 2018 5:14 pm
by Matt
Ah, well glad you got it sorted. Other gremlins...