Volkswagen LT 2.8 litter, during driving while the van is loaded the engine shuts down suddenlly. turning the key off and on again starts the engine back on. what could cause this problem? thanks

need more info does it run warm

Could be a number of things but may want to begin by checking wiring to starter, battery, or even the ignition switch. These components may not turn your engine light on.

Generally you could drive the van for many miles-years.
The main issue is loss of power on the cylinders with valve problems which would put extra load on the rest of the engine.
Once the valves are burned they do not close completely so those cylinders have no compression.
it would be like running the engine with one or two spark plugs removed.
If the van has less than 100,000 miles it might be worth fixing. Otherwise that engine is prone to use oil and smoke after hitting 150k.

Some vehicles have got a sensor which increases the idle when air conditioner is switched on because of the extra load on the engine, this sensor may need adjusting, not sure where it is located exactly, sorry.

sounds like a fuel issue i would recommend replacing the fuel filter it is a cheap and easy fix after that if the problem persists then i would take it to a shop to get a free diagnosis in order to find out if it is your fuel injectors or your fuel pump. more symptoms of a bad fuel system would be extreme drop in rpm when put into drive, choking or sputtering, large amounts of smoke from the exhaust pipe, or complete shut down of motor after running.if you need any instruction on removal and installation of any part please comment back on this post thank you, and good luck.

I HAD THE SAME PROBLEM BUT WITH AN ASTRO VAN. THE PROBLEM WAS WATER WAS GETTING INTO THE FUEL PUMP CONNECTOR UNDERNEATH THE VAN, NEXT TO THE FUEL TANK.THIS WAS CAUSING A SHORT, NOT BAD ENOUGH TO BLOW THE FUSE, BUT ENOUGH TO CAUSE THE PUMP TO SHUT DOWN. BEST WAY TO DUPLICATE THE PROBLEM IS TO FIND THE CONNECTOR AND SPRAY IT WITH WATER WHILE THE VAN IS RUNNING. ALSO DO A WIGGLE TEST, THIS IS DONE BY GRABBING THE HARNESS TO THE PUMP AND MOVING IT AROUND, IF YOU HAVE A LOOSE CONNECTOR OR A BAD WIRE THE VAN SHOULD SHUT OFF.

most likely the module that goes inside of your distributor is bad.i had the same thing happen to me on my astro van i owned a few years ago.i would drive it for a while then shut it off.it would not start until it completely cooled down, then it would start back up right away.i replaced the module inside the distributor( which cost me about 45 dollars at the time)and the van never had that problem again.it would start up every time no matter how many times i turned it on or off.hope this info helps you.take care and good luck, manny

WELL I WOULD TEST CAM SENSOR OR CRANK SENSOR THE CAM SENSOR CONTROLLS SPARK AND FUEL SIGNAL HOPE THIS LEADS YOU SOME WHERE

if you have a maintance free battery check the eye in it if green its okay.if dark or black .battery no good that cause car to quit.if battery good you got a ignition component problem.

try changing the coil- sometimes they get hot and break down- once they cool off vehicle will start and run until they get hot again