We have a 97 Punto 55 S which never starts on the first turn of the key. Over the last month it has decided not to start at all on numerous occasions.There is a good spark and if petrol is squirted into the carb it will fire up.Fuel pump is working ok.Once running it is ok.Been to main dealer with it 4 times but this was a total waste of time.Any ideas please.Tom.
My first check would be the coolant temperature sensor for the engine management system. Can't say for sure where this is located on your engine, but it is usually somewhere close to the thermostat housing or into the head nearby. Resistance across the two pins should be 3,400 to 4,130 Ohms @ 20 degrees C, and 340 to 420 Ohms @ 80 dergrees C.
Let us know how you get on.
Whatever is rightly done, however humble, is noble.
We used to have one of these, and I always had problems starting it, it would catch and die, then crank for ages and ages. It never did it for my girlfriend who's car it was. I eventually found that the driving position and offset cramped pedals made me rest on the sccelerator slightly depressing it, and this seemed to be the cause of the problems.
Sorry you did mention a carb.Fuel pump may not be working properly.But that is a guess the fuel pump will have a relay which if not working properly will do this.I don`t know if it has an alarm/immobiliser.Even that could be a prob.I`d go for relay first
Try giving it about a quarter throttle at the point of trying to start it.
If that works try cleaning the inside of the throttle body and butterfly valve edges with non-fluffy rag and some carb cleaner.
If that doesn't work.. when you do get it to go, does it run on only 2 or 3 cylinders for a few seconds, then slowly recover - with lots of steam from the exhaust??
In that case you may have the beginnings of a head gasket leak which is putting a few drops of coolant in a cylinder or two :-(
By the fact that it starts when you squirt in petrol and it starts shows that it is very likely to be a fueling fault.
Even though you say the fuel pump is fine I recon this is the problem. One stage of operation of the pump operates whilst the engine is already running, the other stage is to prime the system and start the car(this bit bust!).
PS On some cars running out of fuel is a good way of breaking modern injection fuel pumps, the petrol passing through is part of the lubrication. No petrol - No lubrication.