Hello I'm new here and have some questions about this engine.
My brother is looking to get a 1993 Vento with the 1z 1.9d NA engine, it has 288k KM .
What should I look for in this engine ? Are there any usual problems ?
I think you will find the engine is probably a 1Y, a relative of the AAZ. It is basically an AAZ without a turbo. If it really is a 1Z with no turbo then it is someone's swap project - it was never sold that way.
If it is a 1Y then it will be a fully mechanical engine. No sensors or computer, just a very reliable mechanical injection pump. The only major issue that was somewhat common with that engine is the crank pulley coming loose - it starts with a wobble which you can see visually if you look at the pulley with the engine running. It will deteriorate till the timing starts to wander and then eventually it breaks off tossing the timing belt and trashing the engine.