Hello everyone.
I`ve been going through the forum in the hope that something similar will help me. BAsically I have a y reg 1.2 16v sporting. 2 weeks ago the ecu started to flash and the car was juddering. Diagnosis lead to the spark plug leads being changed and fiat reset the ecu. 2 days later the ecu light came back on and stayed on. Took in back to fiat who said there were some old codes in their which they deleted. That morning my heater had packed in so I asked them to look at this too. They said it needed re-wiring the motor had gone and so had hte resistor, cost £300. I was`nt happy with this so I asked an electricain\mechanic friend to have a look. £50 to rehave a new resistor and a connector done, all works well now. However, the ecu light came on again so I contacted fiat again. The engine is running beautifully, no mis-fires, judders or unusal noises. Fiat now say the lambda sensor has gone, but this was replaced under warrenty 2 years ago. I`m inclined not to trust fiat at this time as I feeled slightly conned over them wanting me to fork out 300 for a new heat motor. I`m going to contact my friend again to see what he says, but do you think it is worth my while disconnecting the battery for a while?

Thanks

No. Lambda sensor errors are often recorded after misfires, as the lambda sensor gets coated in unburnt fuel which then oxidises on the surface. If the error is a signal fault then give it the benefit of the doubt and use a little more right foot to help clean it. If the error is to do with the heater circuit of the lambda sensor then this may be due to the misfire causing a premature failure or it could be a connection problem at the multiplug.

Lambda sensors are very tough units and if it is a signal fault will generally recover with use, I have had many fail after headgaskets replacement which after use have recovered.