VW Polo 1.4 - dashboard indicators

[damarisw]

My car is a Volkswagen Polo 1.4, almost 20 years old (Nov 2002), manual gear box, petrol engine. It was imported to Bulgaria from Italy, so the manual is in Italian.

I have TWO YELLOW INDICATORS lighting up ON MY DASHBOARD:
1) exhaust gas indicator (spia dei gas di scarico in Italian)
2) EPC/petrol engine management (gestione motori a benzina in Italian).

I took the car to a service garage in Kyazhevo, Sofia (EM-Komplekt) and they did a computer diagnostic on it, but the result was not very precise. They advised me to change the following parts:
Бобина (х1)
свещи (х4)
ламбда сонда (предна или задна или двете)
гарнетата (крайна и средна)
меката връзка
стоп машинка

They said it was not really possible to say exactly what was causing the two indicators to light up, so changing the parts was partly a question of trial and error.

It was possible to see when the car was raised up that the крайна гарнета is quite corroded, and the средна гарнета is also starting to corrode and the мека връзка is quite worn.

I would like to ask if any owners/drivers of Volkswagen Polos have had the same indicators lights showing on their dashboard and if so you did about the problem and whether changing any of the above parts solved the problem - did the yellow indicator lights disappear?

Thank you for any information. My knowledge about car engines is absolutely basic, so feel free to state the obvious!

Note - I tried to attach two photos of the dashboard indicators and computer diagnostic results but got an HTTP error from the forum so deleted them.