Turning off fuel injection?

[anonymous.shyster]

Is there a way to disable fuel injection for the MicroSquirt? I'm only going to be using it for spark ..

[dontz125]

Don't worry about it - nothing will be damaged if the injector drivers aren't actually connected to injectors. Same with things like CLT, MAP, etc. Just make sure that nothing that will affect ignition performance is left floating - if you aren't using a TPS, for example, be sure to drive it either high (5v) or low (GND).

[mfro]

...if you aren't using a TPS, for example, be sure to drive it either high (5v) or low (GND)...

Or just put identical values into every row of the ignition advance table. That's what I did. Works fine.

[anonymous.shyster]

I intend on running a TPS, but not a map sensor for the present time.

[dontz125]

I intend on running a TPS, but not a map sensor for the present time.

Ok, same idea - ground out the MAP pin to prevent 'float' signals from doing weird things.

[anonymous.shyster]

I'm not sure if there is anything else I need to ground, such as the idle control PWM?

[dontz125]

Ground or pull high any unused inputs. All outputs are ground switching, and any unused can be simply and safely ignored.

[mfro]

I'm not sure if there is anything else I need to ground, such as the idle control PWM?

I do have it running ignition only with only six wires connected: 2xVR-sensor, 2xpower/ground and two coil wires. Works fine.

Regards,
Markus

[anonymous.shyster]

So which of these needs to be grounded: (and am I missing any?)

Spare Input (pin 5)
Flex Fuel (pin 6)
Map (pin 24)
CLT (pin 25)
IAT (pin 26)
O2 (pin 34)

TPS (pin 26) --using this

I'm thinking that only Map (pin 24) needs to be grounded/run high as Map is expected to be used by uS whereas the rest are optional? Maybe O2 aswell?

[dontz125]

I'd ground the MAP input; don't worry about the rest for straight spark. As mfro suggests, you CAN ignore all the inputs except whatever you're using for the tach signal, but you do need to be careful - TPS and MAP can surprise you if allowed to float and not otherwise masked out within the .msq.