injector voltage range 1jz for blitz sbc i colour

[pato]

iam hooking up my external voltage unit, from my blitz i colour, to read my injector %
but i need to preset in the max and min voltage to get this.
anyone know what these values are ? or how i can get them ?

[oldcorollas]

err 12V (14.5 or 15?) and zero volts

[JustCallMeOrlando]

Ya, I'm with Stu. They're either on or off, theoretically 12V-0V but in reality ~13.5/14.5V-0V

[pato]

hmm,,
yea, well like, lol
these are the instructions ive got

"Setting of voltage Data
it sets the displayed unit value and the unputted voltage value to be displayed as a two point relation
advice: eg for pressure sensor FIT value would be as follow
input like AUX : low=0.5 (right arrow) FIT=0.00, High=4.5v(right arrow) FIT=10.0

(FIT value of =10.0 ) x 100kPa ( pressure value)

explanation of input voltage display
input line: aux
low voltage: 0.0 - 16.0V
high voltage: 0.0 - 16V
low FIT value -999 - 9999
high FIT value -999 - 9999"


ok so to clarify, i need to know the voltages going to the ecu from the injectors, that tells the ecu how hard the injectors are working

[JustCallMeOrlando]

The injectors have 12V (or higher when running) going to them and the ECU earths them to open them.

[YLD-16L]

You'd want to measure the duty cycle of the injectors, not voltage.

Those instructions you listed are for measuring sensors eg. a temp sensor range of 0 - 5V or a map sensor range of 0 - 5 etc. The FIT as you describe it is to display numbers somewhat meaningful to that sensor rather than just raw voltage data.

This gadget you have obviously assumes a linear output of the sensor you are measuring.

EDIT: another example of somethign it could sample is TPS and it would simply be 0.0V = 0 (FIT), 5.0V = 100 (FIT) then it would show you throttle % on the display. It'll take a little more research/testing to find the range of the air/water temp sensors for your car.

The injector duty cycle "how hard the injectors are working" input should be as simple as running a single wire to one injector and I can't imagine it would need any calibration like the sensors.

Surely the instructions for that blitz item aren't completely shite?? Although I have heard they aren't all that clear.

[Norbie]

ECU's trigger the injectors by pulling to ground, not applying a voltage, so I don't think this device is going to do what you want it to do.

[YLD-16L]

Norbie, pretty sure that gadget he has does cater for injector duty cycle but he is just confused and/or trying to wire it up incorrectly like a sensor input.

EDIT: It appears it doesn't do injector duty cycle after all:

"The color monitor can show 12 kinds of data, which are BOOST, TACHO, SPEED, POWER, TEMPERATURE (water/oil), OIL PRESSURE, FUEL PRESSURE, AIR/FUEL ratio and External Voltage Input 1-3 (needs optional external voltage input harness). Maximum 6 kinds of data can be shown on the screen at the same time. (Please note that temperature sensors, pressure sensors, and A/F unit are optional items.)"

[pato]

well thanks guys
i think i know what needs to be done,
iam sure i read somewhere that it can do injector duty,
ive found the injector wire on the ecu from the apexi wiring diagram, and iam going to hook it into there, and just see how the voltages change and what not.
if not ill just take it out and run it for something else.

thanks anyway

[pato]

Surely the instructions for that blitz item aren't completely shite?? Although I have heard they aren't all that clear.

no instructions whatsoever in english on the voltage harness, and the only thing in the actual units instructions ( which was also all in japanese, i was lucky enough to find a translated version on sf.) i completely read out to you guys

advantage of going apexi i guess, english instructions

[Norbie]

iam going to hook it into there, and just see how the voltages change and what not.

You still don't understand. It's a pulse-width modulated (PWM) signal on that wire, voltage won't tell you squat.

[pato]

You still don't understand. It's a pulse-width modulated (PWM) signal on that wire, voltage won't tell you squat.

ok,
so how does it work exactly,
the current is earthed from the wire, hence increasing/decreasing injector duty ?

[oldcorollas]

scan the instructions..

[pato]

yea i will, iam also getting them translated by the japanese proffessor at uni hopefully,
will find out tomorrow