Engine light defeated
Ever since I bought my 156 2.0TS Sportwagon in September 2011, it would light up the engine warning light after a 70 mile+ motorway run. When I tookit to my local dealer he charged me £30 to clear it and told me not to worry..... So the next time it happened I bought the lead and used Fiatscan to clear it- IIRC the code was 2077 and 2078 which basically said it was running a bit weak. So I put up with it, sometimes it would clear itself after a couple of days, sometimes I'd have to get the laptop out.
A couple of weeks ago I stuck a bottle of Comma oil's injector cleaner into the tank. It cleared up a slight 'whuddering' noise I was getting at around 2500 - 3500 rpm. I've done four 100 mile ish motorway runs since putting the cleaner in and the light has remained off. So hopefully my weak mixture was caused by a partially blocked injector(s) and the Comma product appears to have cleared it. Usual caveats apply, no relationship with Comma etc.