Spark plug colour question! - italian car related!

[Timmo]

Afternoon Chaps, Firstly appologies for non french content! but as an avid Frenchy driver i htought i May get away with it!
changed the plugs and leads on the good lady's Fiat today, (bravo 1.2 16v) cars been missing badly lately, - always misses but only slight when under load, pulled the plugs out and they were all a colour ive not seen before on plugs, a quick google only reveals the usual Haynes chart but in colour! so thought i'd call on the Collective and see if any of you have any idea's???





plugs were cold by the way, as only time i'd have expected to see them Red would be when they were HOT!
the plugs in it have done a while, but not the recommended service interval, (12k on this one) a bit bemused when i pulled them out and they were this colour!!
if it makes any difference they are 8 on the plug heat scale (ngk)

ta in advance for any thoughts,
Timmo.

[Deanxm]

Have you been running cheap supermarket unleaded in the punto by any chance?
Cheap fuel has cheap additives which leave this red or purple deposit, the deposit is conductive and so ruins the plugs.

D

[Timmo]

Thanks for that matey, we did use tesco for a while as a succession of 5p off L vouchers, but wifes been using a garage on the way to work, was a Jet, now Texaco,
Thinking on the life of the plugs they Would have had More tesco than any other so that may explain things!
Thanks again fella,

[Deanxm]

Its not really a problem, but since the deposits can be conductive it can cause missfires like you were experiencing so its something to watch out for.

D

[CitroJim]

Years ago, and I mean YEARS ago when I was just a lad, Jet petrol had a terrible reputation. My dad would rather run out than use it...

Maybe things haven't improved over the years... As I see it though Jet still appears to be 'bargain basement' stuff like supermarket petrol so maybe the same applies.

Replace the plugs and run on Shell or BP for a few weeks and see what happens...

That's some fine contamination there. You don't live near an iron oxide works by any chance do you? Fine red dust getting in the inlet tract. I ask as we had one near here years ago in a village called Deanshanger and the whole village was stained red...

[CitroJim]

Or, seeing where you are, a china clay works?

[Timmo]

Were much further down from the clay side, although was born in clay area! Were down where there used to be a lot of tin mining, no such production any longer though, still much evidence but no real work happening, wife parks the car at the park and ride on the outskirts of truro, but nothing Really industrial there either, first set of plugs have noticed it on and been servicing it myself for the past 10 years,
I hear what your saying about jet, I think the last of the jet's has gone here now, maybe one left?? But seem to remember pops saying not long back that they had been taken over by Texaco?? Other than the few Privately run forecourts we only have the big named forecourts and supermarkets now! I guess she'll use tje texaco as its on the way to work, but will keep an eye on it,

Has always missed at the 2k mark, tried new coil which cured it for a couple of days, new plugs, leads etc. Make very little difference, cleaned up the main eartjs I could get too incase too and still suffered, may have to bite the bullet and get a genuinme coil! - or nab one out the breakers yard!

[addo]

It's a manganese compound, methycyclopentadienyl manganese tricarbonyl, or MMT.

Not the ogre people imagine, but still a "bodge" substitute for good fuels.

There is cracked diagnostic software for Fiat group products, and the code readers are closer to generic OBD-II spec. I'd suggest getting some real data is the first step in diagnosing your misfire.

[Deanxm]

The earths on the Punto are in a block together in a MK1 xm stylie which is fairly daft, especialy since everything earths through them, if the coils pack up ( you will have two on the 1.2 punto) then you risk killing the ecu too, just had one over last week that ahd done the same thing, manky earth block causing the ecu's to mess about and miss like hell, windscreen wipers coming on with the fan and all sorts of strange stuff like that.

D

[Timmo]

Thanks for that, I'll bear it in mind if I ever buy a punto!
Is a Bravo 1.2 16V. Most certainly runs One coil pack bolted to the side of the head, Big unit, used on some rangerovers I seem to recall, can't quite remember but know its used on a few different make of lump,
There is an earth plate on the back f the coi to head which I cleaed up fr the MOT but unfortunately for me, rounded out the T25 bolt head, the T27 showed primise but likewise, so need to pop up the yard and get a couple of spare bolts then will get it out, space is So tight though, tiny ratchet and attatchment for bits Just clears the lead heads, with the Smallest extension for it Hits the battery! Joy! I'll get it out!
Typically, I've a diagram of the earths in the bravo bay, But, its on the computer that's been at brothers since before christmas for a rebuild! Bless him! I'll have to polish something comical onto his bonnet next time I see him!

[Deanxm]

Thanks for that, I'll bear it in mind if I ever buy a punto!

Doh.

D

[dnsey]

IME, inspecting plugs these days is a far less reliable diagnostic tool than it used to be.
I've seen some really unexpected colours from perfectly-running engines; partly, I suspect, because fuel formulations have changed, and partly because ECU-controlled injected engines don't give as much away as 'crude' carb jobs.

[CitroJim]

Interestingly, I saw exactly the same colour deposits on the plugs in a poorly Clio last night. The Clio in question was running rather rich due (I believe and hope) to a duff CTS...

The owner fills up mostly at supermarkets...

[Deanxm]

I wonder if drinking supermarket brand Coke turns your insides a funy colour too.......................boggles the mind.

D

[Timmo]

Back in the late 90's I hadn't long been working in the pub when cleaning the cellar, boss mentionedthe cider kegs were good but if moved and dropped it dislodges the bung, anyways, paid attention etc. Cleaned the floor All lovely, next morning when walking in, boss had the face! Walked me into the cellar and pointed and the Long purple stain on the floor, seems I'd knocked the tap a little and it leaKed half a keg of Real cider (8.4%. Naturally cloudy Kick Ass stuff!) across the cellar floor, turning the concrete cellar floor Purple! Lord only knows what it does to your insides if it can do that to Concrete!!!