If it idles with the switches unplugged then it sounds to me like the idle switch is either broken or not being closed when the throttle is closed. The switch you need to check is under the throttle body and you can't get to it without taking the inlet boot off. Even then its a right mare as there isn't much room to get to the screws! If you unplug it the ECU will basically think your car is idling all the time so I imagine it'll run really badly, and it wont be able to enrichen the mixture at full throttle either!
Once you've sorted the 2 switches, the Idle/CO procedure on Digifant MK2 is as follows:
1. Get the engine up to temp, at least 80 degrees on the MFA oil temp display
2. Turn the engine off and remove & plug the intake side of the breather pipe between the rocker cover & air intake
3. Hold the MFA button in and turn the ignition on, off and on again, then start the car. This puts the MFA into a 'secret' mode. Put the MFA switch to setting 2 and press the button till you get the digital rev counter, position 2 I think
4. Unplug the blue temp sender and rev the engine cleanly over 3k rpm 3 times, letting it return to idle between each rev.
5. Check the rev display, adjust the idle with the idle screw on the throttle body to about 850-900 rpm. Clockwise to decrease, anticlockwise to increase
6. If you have a CO meter, block off one of the talipipes (i use a load of duck tape) and shove the probe up the pipe. Follow the manufacturers instructions, and set the CO to about 1.8ish using the allen screw on the MAF, clockwise to increase, anticlockwise to decrease.
If you don't have a CO meter, turn the screw in until the engine starts to sound rough then back it out gradually till the idle sounds smooth & even. Check the aerial or bonnet stay for vibration, you want it smooth as possible. This will get you close, then take it to a garage to get it set properly
7. Reset the idle to 850-900 rpm if it has changed, and adjust the CO accordingly, repeat till you get about 1.8 at 850ish rpm
