Technical Coil pack and valve guide.

[fladavid]

Hi.
My daughters X-Region Punto started running badly yesterday,no power from the engine and a noisy and rough idle.
She called the RAC and he said that cylinder No2's spark plug was oiled up due to a worn valve guide and that the coil pack to that cylinder was playing up.He said that there was two coil packs each running two cylinders.
The car has been pretty unreliable and isn't worth much so with that in mind is it worth spending the money on repairing it,what is the likely cost? Also was he correct about the two coil packs?
Thanks.
David.

 

[flisko]

if its 1.2 8v it got two coils

needs to be checked for errors

 

[Brendan W]

There are a number of reasons why a plug gets oiled up.
Worn stem seal, stuck or worn rings or cylinder bore wear. Either will be the wrong side of £400, the latter probably more and looking to a replacement motor with all that goes with that. I'm inclined to think that what the RAC guy meant was stem seal as a worn guide would be fairly hard to diagnose from the outside.
A third possibility is a blown headgasket. Puntos have a bit of an Achilles heel in that department. Repair in a garage is probably going to be £300 ish. If you're handy with spanners and catch it early it can be done for the price of the gasket and some coolant £25 and half a days work.
A simple compression test will tell if it's headgasket or worn bores/rings. Competent garage would do it in an hour.

 

[fladavid]

Just spoke to my dad's mechanic and he said it sounds like the coil pack and because the cylinder isn't firing the oil in the cylinder isn't being burnt off the plug.
He says Puntos go through these coil packs and he is going to swap the good one for the bad one to see if the fault goes to the other cylinders instead before he gets involved and it costs.

 

[s and b]

Just spoke to my dad's mechanic and he said it sounds like the coil pack and because the cylinder isn't firing the oil in the cylinder isn't being burnt off the plug.
He says Puntos go through these coil packs and he is going to swap the good one for the bad one to see if the fault goes to the other cylinders instead before he gets involved and it costs.

plugs dont oil if they dont fire
they get covered in unburnt fuel
if this is left then the unburnt fuel causes what is known as bore wash
dads mechanic needs questioning on his knowledge

 

[Ziggy122]

plugs dont oil if they dont fire
they get covered in unburnt fuel
if this is left then the unburnt fuel causes what is known as bore wash
dads mechanic needs questioning on his knowledge

Agree'd
The piston has an Oil control ring - AKA oil scraper ring

it allows a coating of oil to be placed and removed

If you add too much fuel / No spark = Just petrol in cylinder, you get as above
bore wash - the petrol dilutes the thick oil protecting walls to weak sauce and suddenly heavy metal on metal contact = Bye bye engine

A plug getting covered in oil is due to oil not been controlled
IE blow by / Knackered seals

Ziggy