Ciao fellow 155isti,
I am so bummed... Symptoms are still there, reasons unidentified: driving by cold temperatures (32 - 40 farenheit), injection light comes on, engine fan kicks in, water temperature shows at minimum.
I'm mad because my first elettrauto identified the thermostat as the problem, and changed it. The problem re-appeared after 2 days and I'd realized the guy tried my car over the huge distance of 1.2 km, so I instantly gave up on him.
My mechanic ran a more detailed Bosch diagnostic and came to the same conclusion, except he was professional and showed me the actual error codes. The thermostat was returning "impossible" values and the AFM seemed to not send signal at times.
In went a new thermostat, but the problem showed up again, except the AFM issue didn't show up anymore.
So my mechanic took my car to an elettrauto he trusts, who re-wired the thermostat to the ECU. The car being 12 yo, it makes good sense that some wires are getting old.
Additionally, the ECU started showing errors coming from the Lambda, so in went a new Lambda. Fine, I got the car 70,000kms ago, I can totally believe both the AFM and the Lambda need replacement at this point.
But... This morning I drive my car to work by 32F, and after 7 miles, same thing happens again.
So I'm taking my car back tonight for another Bosch diagnostic, but I'm confused. What's left apart from the thermostat and the wire to the ECU that could go wrong? Faulty ECU contacts? Faulty ECU?