Hi, yea sorry everyone, thought i had gave these details. it's a 1999 1.2 16v engine. Fiats did say they checked all the pin connections. I had checked, and in some places renewed, the earths to engine and chassis. I'm thinking of taking the head of and selling it, as its a new exchange one. and scraping the rest of the car.
Hi,
I feel your pain,
we had to sell a good 6 year-old low mileage car ( not FIAT) with similar issues,
now - in hindsight I wish I'd tried this;
Disconnect battery,
then unplug the lambda sensor,
and MAF sensor, (+ a few other options I'm sure)
wait until the ECU should have "forgotten old faults" - a few hours..,
then start it up without touching the throttle.. supposedly the ECU will supply a nominal value for the sensors it receives no value from ( factory settings..!!)
in theory it will just run with a few nominal values in this "limp-home" mode,
then systematically replace sensor by sensor and see what / when things change,
what's the worst that can happen..??,
I know it's no consolation ..BUT I had no fuelling issues when I did the headgaket on a 2000 1.2 16V,
just major hassle with other bits..,
good luck, and let us know what you find..,
Charlie