It stalls, because the timer unit cannot keep the engine going under any load at all. The instructions on the turbo timer say that you should not even leave the air conditioning running when the timer is running the vehicle because of the extra load. With the key in the ignition and the car running the turbo timer circuitry (for run after key off) is not even invoked. It comes into play with the key off only. The only wiring for the timer is 3 wires on the ignition switch and 2 grounds. It just parallels the ignition switch and provides an alternate ignition path upon keyswitch cutoff, times out and then breaks the parallel ignition path. This particular unit is the Blitz dual unit and I just rechecked the wiring diagram to confirm.
Alan [}
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