xoxide

Alright so background is- I bought a 240sx with a 1jz off a member on here a few months back... It was an unifinished project. Not sure what model 1jz it is, but it is all stock with a chasebays wiring harness and a jdm 2jz-gte supra ecu...

I finally tried to start it and have been having issues, it has spark but the injectors are not pulsing... Im getting 12 volts to all of the injectors, but if I put a test light on the ground side pin and crank the car I am not getting a pulsing light (to see if the injector is working).... Ive heard the 2j ecu wont work with stock 1j injectors, but ive also heard a jdm supra 2j ecu WILL work with stock 1j injectors... I cracked open the ECU and it does not look like anything is fried either...

However, if I spray ether into the intake the motor will run until the ether burns off.

Consequently, the previous owner had the exact same problem with his car (I just swapped the motor/electronics into my car and sold his):
https://www.clublexus.com/forums/per...lp-please.html


Can anyone help me, I am beyond lost and have been researching for hours.

Ali SC3

iTrader: (10)

doesn't matter what type of injectors they should be pulsing as long as they are high impedance OR you have the resistor pack installed in the harness.

You dont want to be using high impedance 1JZ injectors AND a resistor pack that would not be helpfull or work.
I don't know how they set up your chasebays harness, but if it set up for a resistor pack then you need to use low impedance injectors like the US 550's or disable the resistor pack because that is most likely your problem.
when you go usdm 550's which are low impedance then you use the resistor pack.

so let us know how the harness is set up and we can probably figure it out.

another thing is could be is ecu wont fire off injectors if there is no IGF signal from the ignitor.
make sure the fuel pump is coming on as well.

xoxide

There is no resistor pack or provisions for a resistor pack on the harness.

Fuel pump is on an independent switch/relay via a switch panel and is definetly coming on.

Do you know what pin the igf signal is on the ignitor so I can check to make sure it is receiving power or even hooked up properly?

Vrank

iTrader: (4)

Igf shouldn't receive power bud, it sends a signal to the ecu to confirm a firing event. Sounds like either an ecu, or chasebays screwed you.

xoxide

Ill be verifying if the ECU is good or bad hopefully today or tomorrow, im leaning towards chasebays **** up though...

I did read deep into a chasebays review thread that the jz igniters need to have their own ground to the chassis (from the igniter to the chassis) when using the chasebays harness, does that have any validity to it? It is odd that my harness only has 1 ground.

xoxide

Seems as though I found the problem!

I never thought to look, but my MAP sensor was one of those onyx ebay brand 3 bar map sensors, not stock... for whatever reason it was not jiving with the rest of the setup.... Maybe it was bad or maybe 3 bars just didn't mix with the stock 1j,

Anyways I unplugged the MAP sensor and she fired right up... Doesn't really idle with the map not hooked up, but it does run! I plugged the map back in while it was running and it died immediately.. So I guess I need to find a stock MAP sensor.

Ali SC3

iTrader: (10)

yeah the stock ecu can't handle anything else other than the stock map sensor pretty much.
those 3 bars are for aftermarket ecu's I want to say, I know mine wouldn't start with the 3.5 bar without messing with the throttle and then even barely, but unplugged it will start and then die. with the stock map it should start and run so you are on the right track.