earthmoverpdt
New member
I have a 1997 Punto 1100 petrol When cold and warm it runs like a dream but when it gets hot it cuts out at the lights etc i have been told O 2 sensor on carb is duff and its dear to replace any suggestions ?
phil
phil
i mean its a UNO sorry for confusion itsI have a 1997 Punto 1100 petrol When cold and warm it runs like a dream but when it gets hot it cuts out at the lights etc i have been told O 2 sensor on carb is duff and its dear to replace any suggestions ?
phil
Mine's a 97 model bought in Malta, I think they were rated highly and in quite a few countries they continued to be available long after the Punto. Just shows how many people use the forum.
Alex what do you mean by a "switch" is it the idle plunger?OK, Hello - welcome to the Uno Forum
O2 sensor on carb... I think that's way off... Firstly because if it has an O2 sensor (in the exhaust) then it's fuel-injected (no carb). Sorry I'm not trying to shoot you down, just trying to narrow the possibilities
If it is fuel-injected, then yes it may be the O2 sensor. And, I think being a later Uno, it will be fuel-injected - but hang on, a 1997 Uno? They stopped making them when the Punto came along in '94.
There are lots and lots of possible answers to your question...
A common favourite for running difficulties like you describe (cutting out when hot) is the finned ignition module on the distributor, but really we need a little more info. Is it just that the engine won't idle - can you keep it running with the accelerator?
If it's fuel-injected, there's a switch on the throttle body near the accelerator cable attachment (first pointed out by Monty Mort, a member who has now moved on to a Stilo and still fixes it like an Uno!) This switch needs to click 'closed' with the pedal released, as it reduces the amount of fuel delivered by the injector. I can guess that with the engine cold, the extra fuel would go un-noticed, but with the engine hot, it would severely reduce the idle speed. Basically, it needs an accelerator cable adjustment to rectify, but you could also check the switch with a multimeter.
I picked out one of many causes at random - I think we need more info for a convincing diagnosis. I don't have personal experience of later injected Unos and I hope someone can jump in and correct me where needed
So - are you sure about the year? Injected or carburetted? And what type of cutting out - does the engine restart, does it drive OK when moving, etc.
I just thought of a completely different scenario if it's a 1987 Uno 1116cc - the fuel cutoff valve on the carburettor - might be cutting off - but it wouldn't be the valve at fault, it would be the control unit that drives it! You can wire the valve to the ignition coil orange wire so that it's on all the time. However, since you're in the UK - I suspect that most 1987 Unos have safely rusted away...
Thanks,
-Alex
Ah - but the original poster was in England - and FIAT stopped making the Uno for the English market in 1994, so a '97 Uno wouldn't exist in England. That was what I meant to say, but I didn't quite get it clear Sorry for the confusion! (FIAT Brazil also makes the Uno currently, FIAT South Africa/Nissan made the Uno until 2004 if my memory serves).