I have a 1971 B20E retrofitted with Megasquirt 2 on which I am still using the old thermostatic aux air valve for idle control. I have recently been having problems with setting and maintaining idle speed. Checking the aux air valve from the top indicated that it is closing and opening; however, on reconnection of the hoses with the valve in the closed position you can feel that there is a leak through the valve even though the engine is fully up to operating temperature. It also appears that the valve is no longer fully opening. The writing looks like it is on the wall for the aux air valve and I have been considering implementing idle control via an idle air valve controlled by Megasquirt. I was thinking about either the 2 wire Bosch idle air valve from the early 90s B230F engine (0280 140 516) or the later 3 wire Bosch valve which I think was used on the 850 Volvos (0280 140 542). The earlier 0280 140 516 has some appeal as it looks like the hose sizes are the same or very close to the aux air hose sizes on the D jet and the port alignment might make it an easier fit. It is also ½ the price of the later 850 unit which is nice. Does anybody have experience with using these idle air valves with Megasquirt (in particular retrofitting on a B20E) or a recommendation on another valve for implementing idle control? Any particular things or tricks that I should be aware of?