1994 B150 stalling at low idle - calling alloro and others

Hi, first post. Not a mechanic type. Bought a used B150 with 110k kms for a road trip to the US. Vehicle ran great all the way to New Mexico and then suddenly died. Would start again but then died. Took to mechanic who initially thought fuel pump but tried filter first, which fixed the problem for about 20 miles. He then checked the codes and a MAP sensor issue came up. Replaced it and drove fine all the way to Laughlin Nevada without issue. Driving around town in Laughlin it hestitated and wanted to stall at low RPM off the start. Not bad at red lights where I can juice it but bad in parking lots where I barely touch the gas. Mechanic cleaned the throttle plates but problem still persists. Van is fine at regular speeds. Based on browsing this forum, potential issues could be:

Throttle position sensor.
fuel pump.
Crank shaft position sensor
Loose Distributor shaft
Vacuum leak
Chemtool treatment for fuel injectors
Idle air control (IAC)

Does this sound correct? Would would be the order of ruling out the various issues. Thanks in advance fellas.

Edit: forgot to mention, this is a 1994 V6 3.9L 3 speed. Also, it stalled twice when turning. Seems to be worse when the wheels are turned at very low idle.

Stooner

Does yours have an IAC valve or does it have an idle speed motor? If it has an IAC valve you can take those out and clean both it and the hole it came out of real good. Use a rag, Q-Tips and carb cleaner. This usually solves the stalling problem.

Does yours have an IAC valve or does it have an idle speed motor? If it has an IAC valve you can take those out and clean both it and the hole it came out of real good. Use a rag, Q-Tips and carb cleaner. This usually solves the stalling problem.

Thanks for your prompt reply. I'm not sure if it has the valve or the motor. Taking it back to the mechanic this AM and will mention it. If on the off chance it has an idle speed motor, any ideas then?

Does yours have an IAC valve or does it have an idle speed motor? If it has an IAC valve you can take those out and clean both it and the hole it came out of real good. Use a rag, Q-Tips and carb cleaner. This usually solves the stalling problem.

It appears the it has an idle speed motor, which was shot. Replaced and problem solved. Thanks greatly for your advice.

Ok, I'm now in Yucca Valley and my van is stalling again at idle speed again, this time more frequently (problem started suddenly). It also stalls every time I back up now. Also, when in park, there's a buzzing noise coming from the rear of the van. I'm now thinking possibly the fuel pump is going but perhaps a sensor. Any advice would be greatly appreciated. TIA.