Jeep starts up fine and runs well in idle. As soon as I shift out of Park, she dies instantly. I am clueless. Any thoughts?
The problem might be with the Idle Air Control motor circuit. This component is what controls the engine idle under all conditions.
The next time this happens, with your foot firmly on the brake pedal, just step on the accelerator slightly, and then shift into gear. If the engine doesn’t stall when doing this, it’s most likely a problem with the IAC motor circuit.
The idle air control (iac) valve may be ok, but, there could be deposits on the iac valve pintle. Use a carb and throttle valve cleaner to clean the iac valve pintle and the passage it controls. Also, clean the throttle plate and bore.
Any of these things could contribute to your problem.