Before you start the car it will be whatever Google says the temperature is for your town/village
Technical What my spark plugs tell about combustion?
- Thread starter Wasgehabendas
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Technical What my spark plugs tell about combustion?
Before you start the car it will be whatever Google says the temperature is for your town/village
Wasgehabendas
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with a cold engine it should be within a degree or so of google
normally if its out its just oil on it that can be cleaned off with a spray of brake cleaner
Wasgehabendas
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Yes, when engine is cold it is within real air temperature. I already cleaned the throttle body some 8k miles ago. It was in oil, not that much, but now after many miles it is perfect.
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
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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.
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.
You could get the belt put on the correct tooth, and it may run better, enough to live without the big bill.
If the head gasket is leaking, the way to fix this is also cylinder head removal.
There is really no point looking for fault codes, as they are not going to fix a mechanical problem, the emission readings are probably slightly higher than normal, as some of the combustion is inefficient, as the valves are not fully closed when they are supposed to be.
Understanding the engine stroke, induction compression power exhaust, valves opening and closing at the wrong point in the cycle inevitably result in poor performance and valve/seat burning.
Taking the head off replacing seats and valves and refurbishing the head as nessesary, refitting with new gaskets and belt, will in my opinion fix the problems including the oil leak, and should feel like a new car.
But only of you choose the correct garage/mechanic that will do the job properly.
Cylinder head refurbishment it more involved with specific tools, and I would remove the head and send it away to a specialised engineering company to revalve/skim etc and then refit myself, this is what I have done in the past.
It is unfortunate that the first mechanic has caused all this, but the way to fix it is back to basics, fixing the damage that has happened, if you are keeping the car and have the money to fix it.
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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.
Jockcl, I like your post here as I think our original poster has no great depth of knowledge and your solution - to remove and refurbish/overhaul the head - will almost certainly solve his problem (unless there's something we're not being told about or that is unknown at this time like a fuel pressure problem?).
I've posted above about how I think the "head gasket leak" could probably do with a careful looking at (maybe do one of those gas tests on the coolant? and I'm a wee bit bothered though that a timing belt being just one - or even two - teeth out will cause burnt valves and/or seats? although running it like this for so many miles won't have helped and I agree that increased temperatures could be possible.
Incomplete combustion could be picked up on an exhaust gas analyser - which our OP is unlikely to have access to without extra cost - but it would probably show up in the fuel trims/learned values/O2 sensor readings? (he says he has MES).
Absolutely agree with you about finding a good engineering shop and giving them the head to recondition. Grinding in 16 - or even 8 - valves with my arthritic hands isn't on these days! To be honest I doubt if most DIY mechanics would do as good a job as a good machine shop, specializing in vehicle engines, can achieve.
I think this person's big problem, given what's been disclosed to us in posts above, will be to identify a competent mechanic to do the work?
I'd still like to know the compression readings, either, as PB suggests, with the engine as it stands right now, where more than anything else you would be looking for similar figures across all cylinders rather than how high the figure is, or, what they are if the belt is re-timed correctly and then compression tested. As a lot of the preparation work to access the belt is work that will have to be done before removing the head, if the compressions turned out good and the leak turns out to be cam cover and not head gasket, a lot of expense could be avoided? How about a cylinder leak test if valve condition was suspect?
Oh, and a very happy Easter to all.
Although I think head removal is inevitable, I agree it would be worth knowing the compression readings, before and after the belt being set up correctly, which a good mechanic without being asked, would do anyway and want to confirm, the timing wants checked and set up before the head comes off anyway, so doing a compression test is only a few more minutes work, before the head removal is started.
It's interesting that some people don't understand the difference between ignition timing and valve timing, as if they were the same thing, and will go straight to a code reader for the solution, thankfully there are a few of us who can hopefully encourage people on to the correct path, wither they take it is another thing.
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.
I used to work with a guy like that. Head full of theory, little practical experience, of anything. He would theorise for days, or weeks, about any task or project, make his mind up, and then ask people for their opinion. Having made his mind up, he would keep asking more people until someone agreed with his idea, then reassured would go ahead and cock it up. Our boss was a bit like that too. Two stories spring to mind, not for here, perhaps the 'smile' thread.
Having been a workshop based trainer for some of my life and seen the lamentable decline in vocational training, I fear that this is exactly where our universities are taking us.
Reading your stories is much the same as my experience, unfortunate some people are beyond help, but still you try to point them in the right direction, because you want to be a good guy and help them, only to feel like you would have been better off hitting your head against a brick wall, at lease then there would be a sensible reason for the headache that you have.
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.
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.
I think it's just the word "timing" being used in both contexts? Mind you unless you thoroughly understand Mr Nicolaus Otto's cycle you're on a looser before you start?
Going straight to a code reader/scanner without engaging the "little grey cells"? - standard default for today's fitters! (I hesitate to even call some of them mechanics let alone technicians!)
In terms of giving advice I just love this forum because there are so many really knowledgeable people on here where you can have intelligent conversations about problems with people who know what they are talking about but have different view points and approaches - all of which is revealing and edifying. I'm very careful about direct approaches from friends/neighbours. If asked to intervene directly by getting my tools out (not often these days) I feel confident but when asked just for an opinion where some other person is going to be involved in the fix or may already have been involved, possibly with a disastrous outcome where you then find yourself being dragged into the acrimony. Often the conversation starts with "But you said"! That I can do without so I tend only to offer quite vague and general guidance. The only exception being a couple of my neighbours who like to get their hands dirty but have rather basic tool kits and I can lend maybe just one special tool and offer advice and guidance in it's use. What does really sadden me, having spent a goodly portion of my life in and around the garage trade, is when I hear of, or am asked for advice in relation to a "repair" which has been totally ineptly carried out by a "garage" and often at eye watering expense!
Kindest regards
Jock
I would hope the OP would know if it was due to the cam belt
Ie it was perfect before it went in
The fact it hasn’t be confirmed probably points to some underlying issue
Improved with injector cleaner
Improved with new fuel pump
Doesn’t sound very much like a timing issue to me
We need fact. Compression test. Not everyone has the equipment. Garage will normally do one for a small fee
Ie it was perfect before it went in
The fact it hasn’t be confirmed probably points to some underlying issue
Improved with injector cleaner
Improved with new fuel pump
Doesn’t sound very much like a timing issue to me
We need fact. Compression test. Not everyone has the equipment. Garage will normally do one for a small fee
This interests me greatly as I've noticed that you get nothing actually labeled "Fuel trim" either short or long term with MES. The generic code reader embedded in my VCDS package reads fuel trims but, unfortunately refuses to "speak" to the Fiats! However I notice that "Lambda Sensor Integrator" and "Mixture Correction Learning Value" are often available with MES. Also they are quoted in %ages just as you would expect a fuel trim to be displayed. I suspect these are fuel trims but which is "long term" and which is "short term" I'm not certain. I'm "playing with them to see if I can get clarity. Anything you can contribute which might help me?
Cheers
Jock
Not really
Fuel trim is listed under other Fiat models under three letters can’t remember what they are
Can’t find it for a 05 and 06 panda haven’t got MES installed at the moment to try on an 11
