Hi I am a newbie to the site although I have had my Fiat500C Pop for 1 year I purchased it when it was 9 months old so it is coming up to 2 years of age. Here started my problem I asked my usual mechanic to do this I have used him for years and trust him to do what is right. When he tried to change the sparks plugs one literally crumbled as it came out causing the new one to cross thread and not seat correctly so he advised me to contact local dealers as car had very low mileage and was under warranty. We arranged a transporter so as not to try and ram the spark plug down and cause further damage, needless to say spark plugs are not covered by warranty according to local dealer and we cross threaded ! Has anyone had a similar experience because I am not sure how to deal with this and it sound expensive from what I can gather? Would appreciate your feedback in not too technical terms as it takes me a while to get my head around car mechanics Thankyou.
Technical Minnie 14
- Thread starter minnie14
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Technical Minnie 14
Hi and welcome to the forum :wave:.
Sorry it's in such sad crcumstances.
Spark plugs can sometimes break when being removed; anyone working with cars for a lifetime has probably done it at least once. That said, if I were working on someone else's car and I felt there were any chance at all of this happening, I'd stop what I was doing and advise the customer of the risk before proceeding further.
If they do break on removal, best practice is then to strip down the engine, remove the cylinder head and extract the remains on the bench. Attempting to extract a broken plug without first dismantling the engine risks ruining it completely, as it's frighteningly easy for some part of the plug to fall into the cylinder. If this happens and the engine is started, catastrophic engine damage is practically certain.
Cross threading a plug on reassembly is another common error which will also require the engine to be stripped down to correct it, but I don't accept that one necessarily leads to the other - it's possible they're using the first fault to justify the mistake they've made with the second; in truth, only the mechanic who actually did the work knows what actually happened.
Fixing your car now will require the cylinder head to be removed and either sent away to an engineering shop to be repaired, or replaced outright. You're quite right when you say this isn't going to be cheap.
It's absolutely not Fiat's fault, nor is it a valid warranty claim - this problem was caused by the garage who replaced the plugs. Perhaps they were careless, perhaps they were just unlucky; either way, if they didn't advise you of the risk before attempting to change the plugs, then you just might have a claim against them. Otherwise, I'm afraid you're probably going to have to pay for this one out of your own pocket.
Sorry not to have better news.
Sorry it's in such sad crcumstances.
Spark plugs can sometimes break when being removed; anyone working with cars for a lifetime has probably done it at least once. That said, if I were working on someone else's car and I felt there were any chance at all of this happening, I'd stop what I was doing and advise the customer of the risk before proceeding further.
If they do break on removal, best practice is then to strip down the engine, remove the cylinder head and extract the remains on the bench. Attempting to extract a broken plug without first dismantling the engine risks ruining it completely, as it's frighteningly easy for some part of the plug to fall into the cylinder. If this happens and the engine is started, catastrophic engine damage is practically certain.
Cross threading a plug on reassembly is another common error which will also require the engine to be stripped down to correct it, but I don't accept that one necessarily leads to the other - it's possible they're using the first fault to justify the mistake they've made with the second; in truth, only the mechanic who actually did the work knows what actually happened.
Fixing your car now will require the cylinder head to be removed and either sent away to an engineering shop to be repaired, or replaced outright. You're quite right when you say this isn't going to be cheap.
It's absolutely not Fiat's fault, nor is it a valid warranty claim - this problem was caused by the garage who replaced the plugs. Perhaps they were careless, perhaps they were just unlucky; either way, if they didn't advise you of the risk before attempting to change the plugs, then you just might have a claim against them. Otherwise, I'm afraid you're probably going to have to pay for this one out of your own pocket.
Sorry not to have better news.
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A secondhand cylinder head maybe an option too then it's a straight swap rather than removing it and sending off to be machined though of course that does have a small risk due to the nature of the item?
Any decent mechanic should feel almost straight away that the plug is going in cross threaded as you put them in at first with your fingers on the end of a plug spanner, I suspect your guy simply made an error they are tricky to put in as they are all at different angles and face the rear and pipework is in the way too.
As above its a simple if expensive fix.
Any decent mechanic should feel almost straight away that the plug is going in cross threaded as you put them in at first with your fingers on the end of a plug spanner, I suspect your guy simply made an error they are tricky to put in as they are all at different angles and face the rear and pipework is in the way too.
As above its a simple if expensive fix.
+1. I had exactly this thought when I got the quote for the recent spark plug change on my Swift; I let the dealer do the work despite it being very easy for me to do it myself (instructions in the car's handbook easy...).
Not sure how the old one crumbling caused the new one to cross thread but that's by the by now I suppose in any case.
I wouldn't panic too much though; if you've got the 1.2 engine it's likely to be in the several hundreds to have the head pulled and cleaning the thread up (which the spark plug screws into) won't be a big or unusual job for a decent engine reconditioners (frankly it'll be bread and butter work for them) to tackle; in any case there's likely to be a secondhand head easily available if something does go wrong (unlikely). Not thousands. Not starting the engine or trying to force things was a wise move.
The twinair may confuse things as I'm not sure about the supply of secondhand parts for it and I'd imagine it's a lot more involved to get the head off and dealt with.
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Slightly off topic I had the earth electrode( of the spark plug ) break off whilst driving(old Micra ) in the centre lane of a motorway up hill the car immediately started miss firing and you could hear a metallic tinkling sound I had no option but to keep going the noise stopped a mile later, amazingly the car ran fine for another 35000 miles before we sold it with no apparent issues.
The cause was the plug had come unknowingly come slightly loose.
The cause was the plug had come unknowingly come slightly loose.
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I'm assuming a 1.2 petrol here, not the Twinair.
Original plug breaking on removal is irrelevant to any problem fitting the replacement. They are trying to avoid paying for their own mistake.
The plugs in these are well-recessed and difficult to insert at the right angle, as most people's fingers will not reach. So they'll get inserted into a plug socket, and then screwed in. It is difficult to get a straight extension onto the plug socket, so very easy to get the angle wrong. This is what they've done. A good mechanic will use just the plug socket, and turn the plug gently, if not in properly, that can be felt. They've been careless, and now trying to get you to pay.
Car goes back to the garage who broke it.
They repair as necessary, and they meet the bill. They should have insurance for this, or just meet it from their cashflow.
Cylinder head needs to be removed and the plug thread properly repaired. It may clean up to an acceptable state, or may need a helicoil. If they propose a used head, it needs to come from the same age of engine and with a similar mileage. In the 500 you have the 70hp engine, make sure you don't get the head from a Panda or Punto 60hp.
Original plug breaking on removal is irrelevant to any problem fitting the replacement. They are trying to avoid paying for their own mistake.
The plugs in these are well-recessed and difficult to insert at the right angle, as most people's fingers will not reach. So they'll get inserted into a plug socket, and then screwed in. It is difficult to get a straight extension onto the plug socket, so very easy to get the angle wrong. This is what they've done. A good mechanic will use just the plug socket, and turn the plug gently, if not in properly, that can be felt. They've been careless, and now trying to get you to pay.
Car goes back to the garage who broke it.
They repair as necessary, and they meet the bill. They should have insurance for this, or just meet it from their cashflow.
Cylinder head needs to be removed and the plug thread properly repaired. It may clean up to an acceptable state, or may need a helicoil. If they propose a used head, it needs to come from the same age of engine and with a similar mileage. In the 500 you have the 70hp engine, make sure you don't get the head from a Panda or Punto 60hp.
I feel bad for OP in this situation as it is not their fault this happened.
This is a nightmare situation for anyone, and I'd hate to be in that position.
Is there any tips for how OP should approach this garage as id imagine they'll do all their talking to try and pass the blame away from themselves. And if it's a typical garage The people may try to be intimidating as I've had experience of :-/
This is a nightmare situation for anyone, and I'd hate to be in that position.
Is there any tips for how OP should approach this garage as id imagine they'll do all their talking to try and pass the blame away from themselves. And if it's a typical garage The people may try to be intimidating as I've had experience of :-/
