If I do go for a stand alone system how do you get the new wiring harness to match up with the existing sensors and control units, or do they have to be replaced as well?
There are lots of Options for making a new harness.
You use a new bare harness that comes with your Stand alone system. ECU side is terminated with proper Terminals and there is usually a sub- harness for a Relay box ( Fuel pump, ECU Main Relay, Cooling Fans, Nitrous etc ) The sensor ends, injector, etc are bare pigtails and you attach what ever terminal ends you need. Bosch terminal ends are widely available on the internet. DIY Auto Tune carries any terminals and parts you need.
You can also order the new Harness pre-terminated with all the correct ends from DIY Auto Tuning ( or any other supplier ) for additional money.
One of our members ( Fric Frac ) makes beautiful custom made harnesses. He also supplies the bare Bosch connectors ( new style with spring release ) for a reasonable cost. Kit includes enough EV1 connectors for all injectors and sensors, TPS and AFM ( if needed ). Terminals come with unwired terminal pins so you can crimp on the pins to your harness. I find that much easier than soldering wires together and then heat shrinking etc.
Edited by Chickenman, 28 June 2016 - 09:34 AM.