Technical What my spark plugs tell about combustion?

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Technical What my spark plugs tell about combustion?

It only takes a drop or two to mess up the fuelling and cause all sorts of problems

for example

a stutter on acceleration

rough idle on start up that clears with a few revs

there's a long tube inside the inlet manifold that oil gets sucked in to.

Never had a problem on 05/06 but I have need cleaning it out on a 2011. Not sure when the design was changed.


seems quite common with the 500. Probably due to them used more for short school runs.


Take the MAP off. The use a rag to clean the shaft

Weak acceleration appeared after cleaning the throttle body! Also, misfire on cold start up appeared soon after it.

Is there any way to clean the tube inside the inlet manifold?


Small gaps on spark plugs will result in weaker sparks. More likely to cause misfires than sluggish performance. Original 'mechanic' who fitted those needs to be kept well away from.
Plug gaps should be 1.0mm. The full title of your plugs is DCPR7E-N-10, teh '10' denotes 1.0mm.

Sluggishness is typical when the cambelt timing is incorrect. My first action would be a compression test. With incorrect valve timing, these may be low, but still should all be similar. If that's ok, next check the cambelt timing and reset if wrong. Consider a new belt rather than refitting this one.

The timing advance shown by MES is the ignition advance, not the valve timing.

Yes, that is why I keep well away from him. No, I haven't gotten the N-10, only DCPR7E with 0.8 mm. Those that FIAT considers as OEM and first ones when you buy a new Panda.

Is there any way to calculate the valve timing based on data from diagnostics? There are 2 good dealers in my town for cars. One of them said they are not keen on doing compression tests because in that way HT leads may become damaged. The other one who is official dealer said they aren't doing compression tests anymore, not sure the reason behind it, maybe also because of the HT leads or they cannot get much money from it.


Just wondering if, due to inexperience, this is being diagnosed as a head gasket leak when it's actually the cam cover gasket leaking. The cam cover gaskets are known to leak and you quite often see posts on here with people speaking of the head gasket leaking when it's very obvious they are referring to the Cam Cover gasket.

I would also like to be a misdiagnosis, but unfortunately it isn't. Cam cover is perfect, oil was leaking from there but I fixed it some 15k miles ago with Victor Reinz gasket and sealer. They are excellent quality.

It can be clearly seen that oil is leaking where head and block merge.


fuel trim is missing from some Fiat cars in MES

I couldn't find it on a 2011 1.2L panda although my Delphi software can read long and short trims fine

Is there any way to get a free copy from Delphi software?

Check air and fuel filters.

Check that the fuel tank breather is releasing vacuum in the tank freely.
Our diesel retarded a little and was throwing fuel pressure faults every now and then for a couple of years... it was a stuck diaphragm in the breather in the filler cap all along.


Do you have an idea where fuel tank breather is located? Air filter seems good. Fuel filter is built into the fuel pump so it cannot be seen.






Thank you for all the help and sorry that I cannot reply to each comment.
 
1 Weak acceleration appeared after cleaning the throttle body! Also, misfire on cold start up appeared soon after it.

2 Is there any way to clean the tube inside the inlet manifold?

3 Is there any way to calculate the valve timing based on data from diagnostics

4 Is there any way to get a free copy from Delphi software?

5 Do you have an idea where fuel tank breather is located? Air filter seems good. Fuel filter is built into the fuel pump so it cannot be seen.

1 this is normal. The flushed oil gets sucked onto the MAP sensor.

2. remove the MAP clean the sensor with brake cleaner. There I also a hole inside the sensor that fills up. Push a rolled up cloth down the hole. Its fairly long goes almost to the throttle body

3. No. to early 1.1 and 1.2 take the cover off and visual inspect. Later engines with a cam and Crank sensor should throw up a mismatch code

4. No but does come on a CD with some dodgy Chinese interfaces


5. Just test with a short drive with the filler cap off
 
'Morning folks. D'you see what Wasgehabendas did with his post above. quoting several sources and inserting comments between them? I've been trying for ages to do this and several people - PB I think, maybe Charlie too - have tried to guide me but I still just can't figure it out! Can anyone explain to me, in language suitable for idiots, how it's done? Is it the same procedure if you want to break up a single post into sections with comments in between? All this "computery" stuff makes me feel so "old", I just don't seem to have any intuitive affinity for it!
 
'Morning folks. D'you see what Wasgehabendas did with his post above. quoting several sources and inserting comments between them? I've been trying for ages to do this and several people - PB I think, maybe Charlie too - have tried to guide me but I still just can't figure it out! Can anyone explain to me, in language suitable for idiots, how it's done? Is it the same procedure if you want to break up a single post into sections with comments in between? All this "computery" stuff makes me feel so "old", I just don't seem to have any intuitive affinity for it!

hit the multi quote button on each post you want to quote. It changes to a green plus

then hit the new reply button
 

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Yes, that is why I keep well away from him. No, I haven't gotten the N-10, only DCPR7E with 0.8 mm. Those that FIAT considers as OEM and first ones when you buy a new Panda.

Is there any way to calculate the valve timing based on data from diagnostics? There are 2 good dealers in my town for cars. One of them said they are not keen on doing compression tests because in that way HT leads may become damaged. The other one who is official dealer said they aren't doing compression tests anymore, not sure the reason behind it, maybe also because of the HT leads or they cannot get much money from it.

I would also like to be a misdiagnosis, but unfortunately it isn't. Cam cover is perfect, oil was leaking from there but I fixed it some 15k miles ago with Victor Reinz gasket and sealer. They are excellent quality.

It can be clearly seen that oil is leaking where head and block merge

I run the standard "cheap" plugs in both the Panda and my boy's Punto and find them absolutely fine - I don't like the idea of leaving plugs in for years, especially in ally heads, so I pull them every year and double check the gaps - although they seldom need reset it's not totally unknown. I'm very keen on not letting plug gaps open up much as it places more stress on the HT side and can cause problems for the electronics and shorten component life.

I haven't done a compression check in quite a few years because I have a home made cylinder leak tester which I prefer to use - this doesn't require the engine to be cranked and gives a much better pointer as to where the leak, if there is one, is located. However I can't think why you wouldn't do a compression check? just pull the supply side wires to the coils and crank away merrily. Don't just pull the plug leads off though because the ungrounded HT can play havoc with electronics. (remember to keep the throttle wide open whilst cranking) I'm not quite so sure on fly by wire? but you could always chock the butterfly open on these? On the later engines with the 2 sensors (crank and cam) I'm guessing, because I haven't personally experienced it, that you'd get the engine check light flashing and a misfire reported - There have been a number of people who have posted about chasing a misfire code and replacing components all to no avail only to find the timing was out by a tooth. Also, as we know, it often happens following a correctly carried out cam belt change and is "sorted" by doing a Phonic Wheel Relearn.

Is your oil leak at the front (timing belt) end of the engine near the exhaust manifold? I noticed, when I did the head gasket on one or our older Pandas, that's where the oil drilling comes up from the oil pump on the front of the engine and transfers into the head. Ours was leaking there too, although I actually changed the gasket because she was using water.
 
I have had people ask me for advise, then go ask someone else and keep asking more, then waste money doing something someone said that was wrong, I must admit, I should be happy but I find it irritating when they come back and say I was right.


Because people don't want to follow advice especially if it might cost them money, so they will go and ask other people who might give them a cheaper solution, then they go and spend money on the cheaper solution, maybe even try 2 - 3 cheaper solutions and when they've spent nearly as much as it would have cost in the first place to fix the actual problem they concede and get the work done, basically because of their sheer stubbornness now having spent twice as much for the same result (y)
 
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