Got an 2003 Punto 1.2 8 Valve - 65k genuine - well maintained to service schedule etc by myself.

1. Had an intermittent misfire on start up for about 10 days or so, if it appears (which it doesn't always do) it clears itself after a couple of minutes but was enough on one occasion to light the MIL and the code read P0301.

2. Now developed an intermittent starting fault - turn the key and the dash lights dim and the starter fails to turn the engine. New battery, starter motor and spark plugs fitted but still the same intermittent no starting problem as described above (not all the time though). Plug 1 (near cambelt end was 'oily' on removal - not burnt black oily but wet, clean oil?

3. Todays developments - non start due to the above but eventually it fired (its as if the engine locks up then free's itself?) but thick white smoke now pouring from the exhaust - enough to blank out the street when I drove off this morning? Eventually cleared to minimal but not gone completely - parked up and went to work.

4. Came out of work, started like a dream and no sign of white smoke at all - weird? Just restarted the car after about 4 hours parked up - non start due to the above and when it finally 'unlocked' and fired - thick white smoke yet again - fault code now reads P0351 in addition the the original P0301.

So, what next - any ideas coz I'm a bit stumped? Any advice greatfully received!

Could be coil, could be leads.

I'd start with the leads (cheaper), but swap the plug with another to give that a better chance of clearing.

Clear the codes.

If the white smoke persists or if you're loosing coolant, compression test.

Negative lead on the engine mount to neg on battery

Does the car start easier?

ziggy

Earth leads removed and cleaned already, emery cloth used on the body where it earth bots on so all appears clean and shiny.

No coolant loss, no oil in water nor water in oil but the smoke was again tonight really bad - restarted after a couple of hours and perfect again?

Would the leads/coil(s) cause this smoke problem do you think? Can't see any logic in it but it is Fiat electrics I suppose!

Can't see how/why myself. Maybe condensation? Oil will absorb a fair bit of water before it forms mayo.

Still, attack it from the electrical side first.

No, its a poser as it doesn't happen all the time?

Oil filler cap incedentally is clean with no 'white mayo' as you describe.

I have a short video on my phone of the smoke which I will try to upload so you can all see this issue - maybe the starting problem is not linked but it seems too much of a coincedence to me as the faults are sporadic and not constant.

Fed up.com!

Think I've cracked it - head gasket!

Not badly enough for water in the oil etc but enough to leak via the jacket into cyl 1 hence the misfire/fouled plug etc and the non cranking of the engine, depending on where the piston comes to rest when you turn off the engine. If its near the bottom then there is 'oomph' when you crank to fire the engine, however if its near or at the top of its stroke, the ingress of water creates enough pressure to 'lock' the engine, in other words not enough starting power via the battery and starter to 'crank' over!

Well I hope so anyway - looks like head coming off!

andy288 said:

Think I've cracked it - head gasket!

Not badly enough for water in the oil etc but enough to leak via the jacket into cyl 1 hence the misfire/fouled plug etc and the non cranking of the engine, depending on where the piston comes to rest when you turn off the engine. If its near the bottom then there is 'oomph' when you crank to fire the engine, however if its near or at the top of its stroke, the ingress of water creates enough pressure to 'lock' the engine, in other words not enough starting power via the battery and starter to 'crank' over!

Well I hope so anyway - looks like head coming off!

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If you take cylinder 1 plug out after running an leave it bdc so it allows water in, when you next crank itll spray the water out and itll be easy to turn over

Water in a cylinder will most likely hydrolock it and do serious damage

Ziggy

when you come to take the cylinder head off carefully look at the headgasket and you will see it has broken slightly between cylinder one and the water jacket
this is usually caused by poor antifreeze/car stood idle for a long period of time
if you catch it quick ie do the job now you could lift the head up without undoing inlet manifold and everything attached clean head and block up in situ and slide a new gasket in and be back on the road in 2 hours
last one i did car is now on 98000 miles and two years running like this since i did it at 70000 miles and this car only gets distress repairs because its owned by a lass who doesn't spend out on her car till it broked

ass who doesn't spend out on her car till it broked

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Sounds like yer typical Punto owner!