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ms1 injector wiring?


driftz240

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simple question if i had a fsm, but i dont

 

on the stock 280zxt injectors what color is power and what color is ground, i have fat green wires all bundled together "thinking thats 12v power" then small green wires with white or yello stripes?

 

thanks in advance, and is there a website with a 280zxt wiring diagram, not that it helps, the only part of tha harness i have is injector wiring and dizzy connection.

 

also on the 12volt side of the injector harness, i know i have to add resistors, why cant i just add 1 resistor instead of 6? woulnt that do the same thing?

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this is quoted straight from the megamanual:

 

If you want to avoid using PWM with your low-impedance injectors, you can use ballast resistors in series with the injectors. You should use one resistor (20-25 Watts) in series with each injector, otherwise the injectors may not all draw the same current, and the failure modes become complicated and difficult to diagnose. As well, you would need a very large resistor to handle more injectors. For example, if you allowed 2 Amps through four 1.2 Ohm injectors wired in parallel (0.3 Ohms total) to one 7 Ohm resistor, the power dissipated would be:

 

P = V * I = 12.5 Volts * 2 amps x 4 injectors = 100 Watts!

 

If you use resistors that limit injector current to less than 2 amps, you can disable the PWM mode (by setting PWM% to 100%, and time threshold to 25.4msec) and treat the system as high-impedance. To limit the current to under 2 amps, you need:

 

resistor ohms = (alternator voltage / 2.0 amps) - injector resistance

 

For example:

 

resistor ohms = (14.0 volts / 2.0 amps) - 1.2 ohms

 

=> resistor ohms = 7.0 - 1.2 = 5.8 ohms

 

also it doesn't mater if the resistor is on the plus side or negative side of the injector, as long as there is one resistor per injector.

The injectors don't have a positive and negative side either. you can switch the wires and it will work the same.

 

are you building a wiring loom from scratch or are you modifying a original loom. The 280zx origonally came with resitors wired in.

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