Technical Spark plug failure

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Technical Spark plug failure

circolo

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My otherwise reliable 19k miles Panda Twin air, became jerky, hesitant and refused to allow the car to accelerate off ecomode without stuttering.

It culminated in falling into "limp home" mode last weekend. Which reset itself once I'd switched the ignition off 3 times.

However the stuttering off ecomode continued, and when on ecomode felt "different". Not quite stuttering but almost.

In consideration of getting the car to Fiat, and the money/time I'd loose. I went for the "having a go myself" at it. I'd read on here a couple of others that had had similar problems. Pointing towards eventual diagnosis of premature failure of the spark plugs, whereby the electrodes had almost burnt through.

The job is easy, remove the engine cover, and remove the coil packs which are bolted in. Then undo/remove spark plugs with a 16mm thin walled tool. Some tools will be too thick walled to fit the aperture where the plugs are deep in the engine. As the hole is only really 21mm at most in diameter.

Once I'd removed the plugs, I was astonished that the engine was even running. The first plug removed was just a bit dirty/worn. Something I'd expect on a 19k mile plug. The other plug, had almost all the electrode frazzled away! How the little twin air even kept going is beyond me.

Anyway, I've replaced the spark plugs. And interestingly they appear a different ngk number, they're correct as I've cross referenced this with a number of sources. It does suggest to me maybe there's an issue with the "long lifeness" of these Iridium units.

Of course, I'm aware premature failure of spark plugs could be an inherent issue with the engine itself. So we'll see how things go.

Currently, however the car feels better than it's ever felt.
 
Anyway, I've replaced the spark plugs. And interestingly they appear a different ngk number, they're correct as I've cross referenced this with a number of sources. It does suggest to me maybe there's an issue with the "long lifeness" of these Iridium units.

The OE plugs for the 85TA are made for Fiat by NGK and are platinum, not iridium - except on the 105TA (IIRC). The commonly fitted NGK branded ILKR9G8 aftermarket replacements are iridium and (hopefully) should last longer. Time will tell.

On the 1.2/1.4, the OEM plugs are copper, and, er, don't last very long at all. I could express that in another way, but then I'd have to ban myself. :rolleyes:

Replacing the 1.2/1.4 plugs with the nearest Ir equivalent is probably the best £30 you can spend upgrading the car. Mine have lasted over 50k now (in the Panda).

Lots of TA owners in the 500 section have also reported premature plug wear and Panda TA owners handy with the spanners should probably fit ILKR9G8's at the earliest opportunity.

Annoyingly for TA owners, a pair of ILKR9G8's costs almost exactly the same as a set of four Ir plugs for the 1.2/1.4. The oil filter element, despite there being much less of it to throw away than with the spin-on type, is about three times the price, as well as being both more fiddly and messier to change. :bang:

Progress :confused:.
 
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Yes. Been serviced, of course! But they are supposed long plugs. Which means they shouldn't need changing. But they did. The service is every 9k on the Panda Twin air. Just don't know why they're not part of a normal service, and instead have copper plugs.
 
Yes. Been serviced, of course! But they are supposed long plugs. Which means they shouldn't need changing. But they did. The service is every 9k on the Panda Twin air. Just don't know why they're not part of a normal service, and instead have copper plugs.

Copper plugs belong in a previous century and don't get on too well with modern fuels containing ethanol. In the 1.2, they can start to give rough running issues after as little as 5k. Also the labour charge to change the plugs (at franchised dealer rates) is more than the price of the plugs themselves; with typical Fiat markups a plug change would likely add another £100 to the cost of what is already an expensive service by modern standards.

A 21st century approach would be for Fiat to specify a better quality OEM precious metal plug capable of running 60k; it wouldn't add much to the initial cost of the car and would save owners a lot of money in servicing.
 
On the 1.2/1.4, the OEM plugs are copper, and, er, don't last very long at all. I could express that in another way, but then I'd have to ban myself. :rolleyes:

Replacing the 1.2/1.4 plugs with the nearest Ir equivalent is probably the best £30 you can spend upgrading the car. Mine have lasted over 50k now (in the Panda).

Now I see that it explains why my car was acting a bit strange lately especially when cold, at just over 10,000 miles.

I guess I will have to get the spark plugs changed soon then. Just looked up NGK's part list, is DCPR7EIX (6046) correct for 1.2?
 
Yes. Been serviced, of course! But they are supposed long plugs. Which means they shouldn't need changing. But they did. The service is every 9k on the Panda Twin air. Just don't know why they're not part of a normal service, and instead have copper plugs.

Hi, :)
you've confused me there..:eek:

AFAIK they ARE "long-life" and rare metal..

my FIAT / Alfa Indy changed them..I'll not quote the part numbers..,as they change in different cars and Build months:rolleyes:

there are a couple of threads on here (FF) outlining the gist of it.., (y)

Charlie - Oxford - Punto TA
 
Now I see that it explains why my car was acting a bit strange lately especially when cold, at just over 10,000 miles.

I guess I will have to get the spark plugs changed soon then. Just looked up NGK's part list, is DCPR7EIX (6046) correct for 1.2?

Yes - NGK DCPR7EIX is the best match for the 69HP 1.2, and a direct replacement for the 60HP1.2 & 100HP1.4. Differences - the gap is reduced from 1.0mm to 0.8mm, and on the 69HP 1.2, you lose the 0.3mm of extra tip projection that's present on the OEM copper core plugs. It's a sacrifice well worth making to get the benefit of Ir plugs and dimensionally there are no issues with the physical fit.

The smaller gap takes advantage of the better spark propogation and more accurate placement of the flame propogation point from the finer tip and also has the benefit of reducing the electrical stress on the coil pack. On no account attempt to gap a precious metal plug; the tip is extremely brittle and you'll risk both ruining the plug and causing serious engine damage. Some say that even checking the gap is dangerous; certainly you must never use a ball-ended gapping tool.

I've run the DCPR7EIX in both 60Hp & 69HP versions of the 1.2 FIRE without issues; plug life is in excess of 50k miles and the engine's tendency to sometimes give a smoky restart if stopped when still cold is much reduced :).

AFAIK they ARE "long-life" and rare metal..

You'd think the OEM Platinum plugs fitted to the TA would last longer than the 18k recommended plug change interval, but experience seems to suggest they're not as durable as you'd expect, and several folks have reported plug breakdown well before that; if I had a TA, I'd fit ILKR9G8's at the first reasonable excuse.
 
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Just saw Denso VXU22 x4 on eBay for only £38 which were recommended for Panda 1.2. Seems reasonable.

Would that affect the Fiat warranty if they were replaced?

However, I'm having second thoughts about buying Iridium plugs as I think that the first few thousand miles with new engines are hard on spark plugs so they should have been replaced on the 1st service and oddly enough, having driven Panda today, it seemed fine but maybe it has to do with milder weather! :D

Yes - NGK DCPR7EIX is the best match for the 69HP 1.2, and a direct replacement for the 60HP1.2 & 100HP1.4. Differences - the gap is reduced from 1.0mm to 0.8mm, and on the 69HP 1.2, you lose the 0.3mm of extra tip projection that's present on the OEM copper core plugs. It's a sacrifice well worth making to get the benefit of Ir plugs and dimensionally there are no issues with the physical fit.

I just looked up NGK's Partfinder for 60HP 1.2, the gap for standard copper plugs is 1mm and for Iridium ones, it is 0.8mm. Yet they are both recommended for the same engine.

But I think it is more to do with copper being a better conductor than Iridium, therefore the gap for Iridium has to be smaller?
 
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You'd think the OEM Platinum plugs fitted to the TA would last longer than the 18k recommended plug change interval, but experience seems to suggest they're not as durable as you'd expect

They might be as or more durable as other plugs, spark for spark, just not mile for mile.

I'm sure the TA uses a wasted spark, so it will fire the plug every revolution and waste the spark on the blow stroke of each cylinder.

And as it's a twin, it'll end up firing both plugs every revolution.
(2 sparks from 2 plugs per rev)
So it fires all plugs every revolution.

Where as a 180 degree 4 pot will fire a different plug (one of four) every stroke, so two different plugs from four per revolution.
(2 sparks from 2 of 4 plugs per rev, then 2 from 2 different plugs the next rev)
So it fires all plugs every two revolutions.
 
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I'm here thinking I'm going to stick with my fire engine!
 
The top of my spark plug fell off after 17k - set fire to my coil - bounced around inside my engine for a couple of days - then came flying out my exhaust setting off every engine warning light on its way
 
Yes - NGK DCPR7EIX is the best match for the 69HP 1.2, and a direct replacement for the 60HP1.2 & 100HP1.4. Differences - the gap is reduced from 1.0mm to 0.8mm, and on the 69HP 1.2, you lose the 0.3mm of extra tip projection that's present on the OEM copper core plugs. It's a sacrifice well worth making to get the benefit of Ir plugs and dimensionally there are no issues with the physical fit.

The smaller gap takes advantage of the better spark propogation and more accurate placement of the flame propogation point from the finer tip and also has the benefit of reducing the electrical stress on the coil pack. On no account attempt to gap a precious metal plug; the tip is extremely brittle and you'll risk both ruining the plug and causing serious engine damage. Some say that even checking the gap is dangerous; certainly you must never use a ball-ended gapping tool.

I've run the DCPR7EIX in both 60Hp & 69HP versions of the 1.2 FIRE without issues; plug life is in excess of 50k miles and the engine's tendency to sometimes give a smoky restart if stopped when still cold is much reduced :).



You'd think the OEM Platinum plugs fitted to the TA would last longer than the 18k recommended plug change interval, but experience seems to suggest they're not as durable as you'd expect, and several folks have reported plug breakdown well before that; if I had a TA, I'd fit ILKR9G8's at the first reasonable excuse.


Thanks for this advice. This is what I will be doing on my next service because my 1.2 Pop is now out of maintenance plan.
 
Thread revival.
I have IXU22 Denso plugs in the 1.2 which were cross referenced by my local auto shop and Denso's site. Are these the correct plugs for a 2014 1.2?
The VXU22 appears to be a "tough" plug and I'm wondering if the IXU22 is OK as its designated "Power". The engine is definitely more responsive at revs but does still have bouts of hesitation on lower revs and part throttle, less so than with the worn out NGK's. Just don't want the plugs breaking up if they are not up to the job.
Denso actually has reference to both types for the 1.2 Panda 2012+. Perhaps I'm being paranoid.
 
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VXU = 0.4mm iridium electrode
IXU =0.4mm iridium electrode with platinum tip
The tough refers to resistance to wear , more of a marketing phrase than anything else perhaps?

Out of interest why did you choose Denso ?
 
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