Hey there! We are the lucky owners of a 1995 Punto, called Helga. When we bought it she had a problem firing on 3 cylinders when cold. A new set of spark plugs fixed it. Today it did it again!? So is it a plug again or could it be something else, maybe the humid weather in Denmark?? And it also never gets up to 1/2 temp? It's always at a little past 1/4? Stuck open thermostat?? Would be awesome if someone could help me get it fixed!!
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Technical Runs on 3 cylinders on start-up?
Hi.
The thermostat is simple and inexpensive to change.
It MIGHT help with the misfire too..
The thermostat is simple and inexpensive to change.
It MIGHT help with the misfire too..
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The FIRE engines of that era had issues with coil packs. Might be worth swapping them for a new set first.
Pattern parts are only about 20 quid a pair.
Pattern parts are only about 20 quid a pair.
The coil packs work the plugs in PAIRS. When a coil pack fails... it will normally drop to 2 x cylinders
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Good point.
Plug leads first, then. Or swap the leads between packs to see if it moves the problem.
Plug leads first, then. Or swap the leads between packs to see if it moves the problem.
they will fire up on 2 cylinders and run terrible so could still be a coilpack.
fire it up once its got dark out and look for little blue sparks around coils and along all the leads to the plugs. If you see any little blue sparks change the leads.
Plugs should be fine for a long time but worth inspecting them visually for cracks in the ceramic coating. And a cylinder not firing will in not much time coke up the plug so whip them out, check them and if ok give them a clean and check the gaps as that can never hurt.
The thermostat probably needs changing, if they are stuck open you'll normally find at idle it will eventually get upto temp but as soon as you start driving along at any speeds it drops back down below operating temp. The stat is one of the weak links on the engine and usually the cause of blown head gaskets so dont just get a cheap pattern part, on these engines you want to always get a genuine part.
Keep us posted
fire it up once its got dark out and look for little blue sparks around coils and along all the leads to the plugs. If you see any little blue sparks change the leads.
Plugs should be fine for a long time but worth inspecting them visually for cracks in the ceramic coating. And a cylinder not firing will in not much time coke up the plug so whip them out, check them and if ok give them a clean and check the gaps as that can never hurt.
The thermostat probably needs changing, if they are stuck open you'll normally find at idle it will eventually get upto temp but as soon as you start driving along at any speeds it drops back down below operating temp. The stat is one of the weak links on the engine and usually the cause of blown head gaskets so dont just get a cheap pattern part, on these engines you want to always get a genuine part.
Keep us posted
a little update. I have changed the leads, and sparkplugs has been swapped out for a set of Iridium spark plugs BUT! i got a little curious, and checked the large oil breather pipe that connects to the airbox. AND, in was a metal pipecleaner, more or less blocking the pipe, took it out, cleaned the pipe, and before putting it back in, checked the hole itself. COMPLETELY BLOCKED?!.. so thats cleaned and pipe back on. she runs like never before now! so im hoping she's fixed i might clean the - connections as well just in case today
BUT! i got a little curious, and checked the large oil breather pipe that connects to the airbox. AND, in was a metal pipecleaner, more or less blocking the pipe, took it out, cleaned the pipe, and before putting it back in, checked the hole itself. COMPLETELY BLOCKED?!.. so thats cleaned and pipe back on. she runs like never before now! so im hoping she's fixed i might clean the - connections as well just in case today
that little thing is meant to be in that pipe, soak it in some kind of solvent to clean it or just buy new one..
Ricambio sell them for few quid
http://www.ricambio.co.uk/69-fiat/6...6-classic-panda-uno-cinquecento-punto-new-500
Ricambio sell them for few quid
http://www.ricambio.co.uk/69-fiat/6...6-classic-panda-uno-cinquecento-punto-new-500
well a vac leak after the throttle butterfly would cause a high idle so if its idling properly does leave much. Could it just be that it sounds different because the crankcase can now breath?
Found a lose vacumhose on the airbox, so no noise now �� but we drive about 45km without that flame trap, and it was down to half the oil?? So I have cleaned it, to good as new, an reinseted it. It didn't use oil before I removed it?
it shouldnt really loose much oil. The flame trap is there to slow the oil vapour being expelled which means alot of it should then drip back in the engine.
If its defo not coming out somewhere else, this kinda points towards there being a lot of crankcase pressure, which might be the reason that pipe got blocked in the first place... Not great news really.
Excessive crankcase pressure could be (in no particular order) worn piston rings, blown head gasket, leaky valve seals (particularly exhaust valve seals), damaged cylinder walls.
Sounds like time to compression test it to me. Gone or going head gasket, depending on where failing could be root cause of it not firing right when cold too and dodgy thermostat could be root cause of head gasket issues. Its all speculation without doing some testing though
If its defo not coming out somewhere else, this kinda points towards there being a lot of crankcase pressure, which might be the reason that pipe got blocked in the first place... Not great news really.
Excessive crankcase pressure could be (in no particular order) worn piston rings, blown head gasket, leaky valve seals (particularly exhaust valve seals), damaged cylinder walls.
Sounds like time to compression test it to me. Gone or going head gasket, depending on where failing could be root cause of it not firing right when cold too and dodgy thermostat could be root cause of head gasket issues. Its all speculation without doing some testing though
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Those spark plug leads with no metal inside can give trouble. I changed mine for solid copper wire with silicone insulation, no further trouble.
