4agze wiring and ECU

[keiichi]

I was doing ok until "If you want sequential you can run MS2X and extra boards for 3/4 injectors and another for 2/3/4 coilpacks and you need the board for the second reluctor input."

[Skylar]

You need to read the previos sentence too if you want that to make sense, so it reads:

"MS2 only has outputs for distributor and two for injectors. If you want sequential you can run MS2X and extra boards for 3/4 injectors and another for 2/3/4 coilpacks and you need the board for the second reluctor input."

MS2X is an optioned out MS2 which allows you to take logic signals from unused pins on the CPU. These signals are very low current and only 5v. You need the boards to boost the signal to 12v plus throw some real current at an injector. You solder into some points and run these to separate boards that mount inside the ECU to run your 3rd and 4th injector. Same deal for the waste spark/sequential spark. Take unused pins and condition the signal so it can trigger a coil to spark. Not really needed if you go and raid 3 Camiras for Bosch 008 ignitors. The spark output on a MS can directly drive a coil without an ignitor, up to you if you want to run external ignitors or solder up a board that does the job of the ignitor.

The last bit about the reluctor: Toyotas run a variable reluctor pick-up/sensor in the distributor to sense the rotation of the wheel. This signal requires conditioning through a LM1815 chip and a bunch of resistors and capacitors needed to make the chip function in the correct mode. The MS v2.2, v3, and v3.57 PCB's only have one signal conditioner. The newly released MS3 daughterboard has one built onto it while the MS2 daughterboard doesn't.

[keiichi]

wow, why would MS only be able to read two injectors, you think they would set it up to atleast read four

that actually makes sense now. so, if one were to spend a bit extra on a more commonly used thing like haltech or something, it would come with built in gear for atleast 1-4injectors, 1-4coilpacks etc yeh? getting an MS does sound like a bit of fun though and a good learning tool.

[keiichi]

also i called the previous owner to find out what the old ecu was.... injen he said, looked them up, they dont make ecu's (b-_-)b


btw... anyone know how to tell if you have low or high impedance injectors?

[Skylar]

The two fuel outputs and single ignition output are plenty to run a 4A. The. 4A ecu only has one fuel output and each injector squirts a quarter of the required fuel 4 times a cycle.

Adaptronic can do seq. spark and fuel, microtech lt8x or whatever it is these days is also four cyl seq. Haltech probably has a 4 cyl seq model but I dunno what it is off the top of my head. Or you could get an ms3 which is capable of running 8 cyl seq.

Impedance is resistance, you know how to use a multimeter right?

[keiichi]

ah yep so check the ohms resistence if it is about 2.5-3.0 its low if its 12ish its high? do i need to turn the car over or just whack the meter on?

[Skylar]

Just measure the across the two pins on the injector.

Yeah, they say below 4 is low and above 11 is high. Something like that, I know I'm not spot on about the numbers but it's thereabouts.

[keiichi]

cool, just checked it, they are 3.7. then i tested the connector and it was 3.7 aswell - would i be correct in assuming that the correct resistor is installed somewhere along the line?

i better go do some work but ill be back with more annoying questions for you or whoever wants to get involved

[Skylar]

"then i tested the connector and it was 3.7 aswell - would i be correct in assuming that the correct resistor is installed somewhere along the line?"

Ya lost me here. You measured the connector while on the injector or the plug alone? It sounds to me like you were measuring the output impedance of the ecu.

What resistor are you talking about?

[keiichi]

i measured the injector alone then the plug alone.

i read somewhere that if you have low impedance injectors you need a resistor or you'll burn the ecu. i assumed that if the plug had the same impedance as the injector the circuit is resisted so the ecu didn't get burnt.