Every time we make a shart right or left turn the engine on my van stalls. It has to be completely restarted. In the last year we replaced the trans and steering column and had a major tune-up. So far, no one has been able to diagnose the problem.
Have you checked the ignition switch?
How do you suggest we check it?
What year Ford? How many miles on it. What kind of maintenance history? Like a transmission fluid change along with filter.
You do need to report the basics, especially the state of maintenance. The power steering puts a load on the engine. Cutting the steering puts a whole bunch of load on it all at once. If everything isn’t up to snuff this kind of thing can stall the vehicle. Spark plugs, wires, fuel and air filters? Basically I’m saying that whether you realize it or not the van is probably not running particularly well - basically borderline.
The problem is that “major tune up” doesn’t mean anything specific. So report the specifics.
Check the switch that’s located on the pressure side of the power steering pump system. Probably located on the pressure line from pump to gear or maybe pump to brake booster. When you go to max steering pressure, it puts an extra load on the engine. This extra load is compensated for by raising the idle which is done by the computer being told by the switch to do so.