Afternoon gents, i have a 2005 vw caddy club bakkie the one with the velocity dash. The engine just cuts out, it cuts out on the spark, i can drive 1km to 600km its completely random. Fuel to the carb is perfect. It was at vw for 5 months and they could not get it solved. Do note the module unit is the black one that needs to be encoded. vw could not get the new one encoded and thus not solving the my problem. I have changed the distributor cap, rotor and bogie cords, checked the fuses next to the battery and all earth points, all is in order and still nothing. Please help!!! Fuel and matches are starting to get pulled closer.

does the caddy have any aftermarket alarm or immobiliser fitted.
does it have a 3pin block coil or the long cylinder type coil, if it has the 3pin block coil then there is no module for the spark, since you have the new dash then the black module that Vw is referring to is the boardznet module but that shouldn't be controlling spark.

there is no aftermarket alarm or immobilizer fitted. Its got the three pin coil. The black box as i came to learn is called a tci unit and there is no other form of "module" or controller on the vehicle. When it is plugged out the car doesnt start because there is no spark without it but the engine turns and fuel goes thru the carb, when you plug it back in the car starts. Ive been scratching for about a year and everyone who has looked cant figure it out either.

take a picture of the black box you talking about because if your car as a 3pin coil then it will not have a tci unit, the 3pin coil has a built in tci unit

These kind of issues are the worst.

Otherwise a relatively simple engine, surely a competent mechanic can sort it out.

Perhaps linked to heat, damaged part that only malfunctions when it's expanded to a certain degree, which would make the failure totally random. Or a similar fault that's linked a certain set of circumstances for it to fail, heat/revs/pressure etc.

When the car cuts out how do you get it running again?
That could also point in the general direction of the location of the fault.