Megasquirt - Total Noobie Questions

[LanciaMad]

Trying to get my head around megasquirt ecu system.

1. Do you remove your exisiting engine loom or leave it in place?

2. What happens with the likes of the immobilizer (key code, mk2 punto) when you have removed the original ecu.

3. Why would you use a relay box?

4. When actually tunning the car, why do you have to do it? Cant they make some software which will tune the car itself?

5. What are the advantages of buying a pre-made box or making your own?

Confused.:bang:

 

[jug]

http://www.megasquirt.info/

1. leave it in place and cut into it to access sensor wiring for existing sensors that will be used, for any new sensors you add you will need to lay new wires.

2. you lose the immob. remember megasquirt is just the fuel injection controller, you need to sort out everything else yourself. if you want an immob you'll need to install one. if you want your sparkplugs to spark you also need to install something to control that. you also want your cooling fan to work, etc etc etc etc.

3. to make the wiring installation easier. if you dont then you still need to do the wiring but you need to DIY it and add your own relays and fuses. personally i would not waste money on the relay board when the cost to DIY is going to be a few pence.

4. there are many software tools to use during tuning (megatune is one). the tools wont tell you what setting to use, for example they cant tell you the PWN criteria to use because they cant tell you if you have low impedance or high impedance injectors, how on earth could they?

5. premade is easier, and the only option for people without the skills to make one, although if you lack those skills you will not be able to do the rest of it either so there is no excuse for buying pre-built imo. self build is more fun and costs less.

to be honest there are much cheaper, easier and better ways to get the same overall results, the advantage of megasquirt is it is fun to install and set up if you like that sort of thing, if you dont then its a bit pointless imo, especially on a car that already has efi and can have the ecu's map modified.

 

[100hpJames]

Member 'kritip' is building his own megasquirt ecu, I'm sure if you get stuck he'll answer your questions via a PM

 

[arc]

doesnt the mk2 punto have a body computer as well? i've no idea about any sort of CAN bus interface on the MS, i never needed it so never read into it.

 

[jug]

doesnt the mk2 punto have a body computer as well?

yes, the "multifunction timer unit" as fiat call it. it doesnt do much if you check the wiring diagram. it does use CAN bus.