The kick-stand switch or clutch lever switch have failed.
what causes a boat motor 40 hp to stall when it is put in gear
Is your clutch bad or wearing out ?
it sounds like ur clutch went out in it.
This is usually caused by a faulty seat safety switch.
torque converter or solenoid problem most likely if it runs out of gear ok.
The vehicle would stall when put in gear would be the fuel pump. The fuel pump is very weak which would explain why in neutral the vehicle starts if it gear it would have to have more gas.
Hey tom its a 1990 pontiact transport van and it starts out fine and as soon as the vehicle warms up it will stall it will start back up but when you put it in gear from park it stall again until cool?
It could be an issue with the torque converter.
Could be time for a tune up.
vacuum leak,map sensor
Try checking the intake manifold or carby for a vacuum leak.
My sons did the same thing until I cleaned the carb out and adjusted it properly.