Punto S - firing on three cylinders - single injector - plugs OK ,leads OK , red light to dash injector icon on ,any constructive suggestions welcome.

Haynes manual suggests taking it along to the local dealer , don't know why Haynes bothers publishing books any more , you could just buy a card off them with the words inside "take long to your local dealer" for all they're worth now! not very helpfull at all.

Thanks All [8D]
Mik







Mik

Bit difficult to say from here, but usual things to check are lambda sensor, coils and map sensor. Check that you haven't got any loose or waterlogged connections in the engine bay too.

Pete.
Cinq sporting 1242cc
http://mysite.freeserve.com/close_to_cracking_up/

I agree with Pete but can you isolate fault, is the misfire at all speeds?, is it limited to one cylinder? is it worse under load?
If the problem is ignition unburnt fuel may be upsetting the lambda hence red light. Check your plugs pull them all out and keep them in order look closely and see if they all look the same colour (In the fire engine 1 & 4 and 2 & 3 should have similar deposit colour. is one wet and is it petrol, oil or water...the odd one out, if there is one will indicate faulty cylinder. recheck plug leads and change affected plug don't assume that a plug will work just because its new they can be faulty too! I think if you had a faulty coil two cylinders would be affected as each coil fires two cylinders.
If the misfire is more general it may be worth trying a dose of injector cleaner through the system it won't hurt..Do not run with a misfire it will destroy your cat.
One last thing you could try is to disconnect the battery for a minute or so and reconnect this will reset the ecu to a baseline and may help but I suspect a trip to the dealer will be required if none of the suggestions offered so far help.
Peetie

Most likely to be false air sucked in at the inletmanfold either by a loose or cracked hose on the manfold or the gasket between manfold an engine.
Geert