Hi. My 02 punto had a flashing ECU light. It started after the dealer changed the timing belt (570 Euro, - £400 - to change the timing belt and service it by the way - is that a lot ?). The dealer "reset the ecu" when I took it back, free of charge, but it made no difference.

Just got it back again. I'm another 120 Euro (£85) lighter now. They said they cheked the valve timing - already sounds like I'm paying them again to finish/recheck their last job of changing the timing belt; They ran the diagnostics and sent the results off to Fiat central, (wherever that is ) and Fiat said to realign the phonic wheel (whatever that is ). They also reset the ECU. Again.

Does this sound like they knocked the timing out themselves when they changed the belt, and have now charged me to fix their mistake ?

I don't know what a phonic wheel is. Is it the sort of thing you knock out of timing when you change the timing belt ?

is the phonicwheel not the wheel with all the notches cut out of it?? As that is what tells the ecu how many rpm the engine is doing etc.

I'll be honest, it all sounds a bit expensive for what's been done :O

I have had this a couple of times during cam belt changes at my dealership, we now make it policy to carry out a phonic wheel learn procedure after the crank pulley has been removed.

Basically the ecu needs to know the signal produced by the phonic wheel (on the crank pulley), if this signal changes from the pattern in the ecus memory then the ecu can interpret this as a misfire, and the efi light will flash and usually a pair of cylinders will be displayed as having a misfire, even though the engine runs smoothly.

Personally I would ask for your money back for the second repair as the error occurred entirely due to the work being carried out originally. If they had carried out a phonic wheel learn procedure then you would not have had a problem.

I will

Thanks for the insight. I understand now - the phonic ring wasn't necessaraly physically moved out of alignment.

How can I, as a mere punter, attribute my sudden source of insight into phonic rings, to give it credability ?

I would like to say to our Fiat delaer, "I was talking to a Fiat dealership in the UK and they said that the phonic wheel learn procedure was required as a direct result of changing the timing belt" ? Are you cool with that ?

Out of curiosity, it's that shiny brass-coloured cog on the end of the crankshaft that you can see when you open the bonnet, right ? Got a sensor looking at it.

Thanks for the great reply. I only donated a quid to the forum so far. If I get some money back from the dealer, I'll top it up the the 'normal' fiver.

You are more than welcome to say that you have conversed with a Fiat DET regarding this problem. The reason the learn procedure is required is that the crank pulley doesnt go back in EXACTLY the same position, this is not due to poor workmanship at all its just physically impossible to get the pulley back exactly as before. The gap between the ring and sensor should be set at 1mm so if the position changes by a tenth of a millimetre then the signal is effected.