The quality of any EFI install - not just a Megasquirt system - ANY EFI install is only as good as the wiring.
If the quality of the wires used, the various connections, joins, soldering and plugs are not 'top notch', it's always going to be unreliable and troublesome,
and be a constant disapointment with you trying to track down problems and issues. The benefits of a professionally made wiring loom cannot be over stated. 
Good Stock
Megasquirt V8 MS1X Loom
The MS1 and MS2 Looms both share many of the same parts, but both are built to the same very high quality and exacting standards.
For example, all our looms have their own independent Relay Box AND Fuse box built in. This means it's a safe loom - with all the fuses and relays profesionally set up, and making for a super easy installation. Similarly, If you are familiar with Rover V8 standard loom wiring, you'll know that the plugs fitted to the 8 injectors are near impossible to get off without risking damage - so, all the injector plugs on both our looms have the 'sprung type' plugs making on / off simple operation - and safe from damage. To make the install as easy as we can, all plugs and all wires are labelled with heatshrink as to what they are and where they go. ALL plugs and connector are new - ( With the exception of the MS1X Loom which uses an original EDIS 8 Module and plug which is fitted as not avaiable new ! ) There is also on the main + Battery feed wire a HUGE 'Maxi Blade' fuse, so, if you do something really daft like a spanner over the battey etc the maxi fuse does its job and saves your wiring loom ! The MS1 looms are fitted for 'PWM' Control, which if you don't fit we suggest you tape up the plug to make it waterproof etc, but should you wish later - its all there. All our MS1 Looms can come with or with a Tacho / Rev Counter feed built in. Detail is everywhere - for eaxmple the 'Coolant' sensor plug is Blue vs all the numbered injector plugs being Black, the VR sensor plug is Grey and labelled, and the PWM Controller plug is Brown. It is as 'Plug n Play' as we can possibly make it. The wires you need to conect are. Main Battery 'Positive' and 'Negative'. Fuel Pump (2 wires) and your TPS on the engine - which is one of the few parts you use - 3 wires into a plug (supplied and fitted to the loom itself. ). Lambda Sensor wires - should you want / have to use it - (if you can don't ! - 'Lambda' and 'Cats' sap BHP !!) oh - and lastly and a Rev Counter wire should you want - Everything else is a new labelled plug !
