I, I have a Fiat Siena vehicle for 10 years, a few days ago I felt a small fault, I took it to the workshop where they checked it and they told me that the spark plugs had problems and that they had to be replaced.
I bought spark plugs and cables to take advantage of replacing them at once, since according to the vehicle's use manual it indicated it by the mileage traveled, I took it back to the workshop to make the corresponding change, the replacement of the spare parts was very fast, We tested the vehicle and it worked well the intonation was perfect.
The vehicle worked perfectly for 15 days, suddenly began to shut down every time but only after I had time rolling, I took it back to the mechanic and everything went on and the vehicle did not go off, he indicated that he did not feel any failure that was suddenly I did not do the changes of the march well, I took it, I rolled it a few days and the fault started again, again at the workshop.
Again the mechanic checked him but at this moment the vehicle went out and several times, then he began to disarm the injectors and clean them, then the gasoline filter was changed. I took the vehicle and after a few days again the fault began but steadily.
The mechanic could not believe what was happening, he started by trying all the sensors and the fault was still going on, at that moment I spoke with a friend and explained what was happening, he told me that this happened a few months ago with his truck and that it was the new spark plugs, that it was best to clean, calibrate the used spark plugs and place them again until getting good quality, the mechanic being a specialist and with many years of experience said that it was impossible, I insisted and did what My friend said the vehicle really began to work without fail.
I already have more than 6 months using the vehicle and without any failures, it is incredible that sometimes even the experts in vehicles detect the faults that seem very elementary.
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