Q: 1990 Subaru Legacy 2.2L code 35. Replaced purge solenoid valve. Idles fine. while driving any speed randomly shuts off. 1992 Subaru Legacy

Hello - the first thing to check is whether the code 35 has cleared, and whether any codes remain. As you mention, Code 35 is a failure with the evaporative emissions purge valve circuit. Since you have replaced the valve, any remaining code 35 might indicate a wiring or connector issue with the purge valve (we will assume the new valve is a good one). The "sudden shut off" may be due to something else that isn’t leaving a code - like a failing crankshaft position sensor. Without it, your engine has not ignition timing. It may fail hot, but work again when it cools off (for a while). Checking for spark at the plugs when it shuts off would be a useful diagnostic step. I recommend a stalling inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.