Missfire?!?!?!?!

[Liam Gunby]

Hello guys and girls,

My 197 has recently developed a misfire.
I have just put a Toyo sports exhaust system on and it seems to have made the misfire worse....

It only happens between 2200ish and 3000ish. Then it clears. Plus only when half throttle or more.

Plugs were only changed 3tho ago with its service.
Not had it plugged into yet as been busy with work but if anyone has any ideas or had it before i am all ears?????

Thanks alot.

Liam

 

[suj]

Sure you are not describing the "flat spot" that comes from fitting any aftermarket exhaust items?
If so best way to overcome it is a remap, search on here, it has been covered many times.

 

[Liam Gunby]

It had a flat spot yes, but this is defiantly a misfire...
It splutters and pops n farts until it clears 3k then goes again fine after.
But as i say when you just drive slowly it doesn't do it. Only when you want to accelerate at anything more than a crawl it happens.

 

[Pav]

Have you tried the map sensor trick?cable tie it...maybe a faulty one..also check spark plugs and coils...

 

[suj]

It had a flat spot yes, but this is defiantly a misfire...
It splutters and pops n farts until it clears 3k then goes again fine after.
But as i say when you just drive slowly it doesn't do it. Only when you want to accelerate at anything more than a crawl it happens.

I was going to suggest what Pav said, but could just be a coincidence that something has gone at same time, like coil pack, camshaft or crankshaft sensor.
Have you had the car read for any fault codes?

 

[Liam Gunby]

Have you tried the map sensor trick?cable tie it...maybe a faulty one..also check spark plugs and coils...

i think previous owner did this. i was confused when i saw it cable tied. ha

I was going to suggest what Pav said, but could just be a coincidence that something has gone at same time, like coil pack, camshaft or crankshaft sensor.
Have you had the car read for any fault codes?

and i haven't had it plugged in to yet no, hopefully can this weekend by my mate and his SnapOn kit. ill give the plugs anoter look, is there anything i can visually check on the coil pack?

thanks for the help guys

 

[Pav]

the spring inside may be loosen or the rubber seal on top damaged (although this shouldnt effect its performance)..

 

[turkie172]

As long as you can repeat the problem every time then it should be easy spotted but I have to say the Renault clip is more accurate about what's wrong. On the 172 I kept getting limp mode and the after market error code reader said it was emissions but the Renault clip said it was the heater in the second lambda right away. Simple things like take the plugs out and look at them and check for oil the spark plug holes after oil change and the oil was spilt on the head. I change the oil between services and am very careful I only let someone else do it to keep the service stamps but was shocked when I went to change the plugs and they were like toffee apples pissed off is not a good enough word for it. If the manifold was changed then the forward Lambda was worked with that affects fuelling might not be tight should have an affect on fuel consumption. For the price it maybe cheaper to buy a new one and fit than spend the same money for someone to look at it. I think you need to give us the full background about the manifold change and how it was running before that was done or the point when this started to happen.

 

[Liam Gunby]

It wasn't the manifold that was changed. just cat back. i have never touched the manifold. The second lambda has one of them extension sleeves on it so shouldn't have a problem with that as i have always used them on my cars.
There shouldn't be any oil in the plug holes but if there is what does that mean? just spilled?
And before the exhaust id say it misfired every now and again with the flat spot but nothing like it does now.

the spring inside may be loosen or the rubber seal on top damaged (although this shouldnt effect its performance)..

I will check that when i can

 

[turkie172]

When I saw Toyo sport I assumed it was the manifold so the second cat has been removed oil in the plugs can affect the electric transfer (oil is an insulator and not for heat) and life of the plugs that's why they don't fill them with oil in the factory just sloppy mechanics can't pour oil into a hole. Now a misfire should be there all the time so without knowing your abilities are you sure it's not the flat hesitation that your feeling next time it happens try instead of pushing the accelerator to power out of it lift off and bring the accelerator in more slowly and see if it's a quicker solution. A misfire the engine note will change the car can also detect misfires and if that's not happening then the exhaust has exaggerated the flat spot and needs mapped out and a Renault sport dyno man maybe the best person to pinpoint your problem as long as you are going to buy mapping service from them.

 

[Liam Gunby]

When I saw Toyo sport I assumed it was the manifold so the second cat has been removed oil in the plugs can affect the electric transfer (oil is an insulator and not for heat) and life of the plugs that's why they don't fill them with oil in the factory just sloppy mechanics can't pour oil into a hole. Now a misfire should be there all the time so without knowing your abilities are you sure it's not the flat hesitation that your feeling next time it happens try instead of pushing the accelerator to power out of it lift off and bring the accelerator in more slowly and see if it's a quicker solution. A misfire the engine note will change the car can also detect misfires and if that's not happening then the exhaust has exaggerated the flat spot and needs mapped out and a Renault sport dyno man maybe the best person to pinpoint your problem as long as you are going to buy mapping service from them.

Im a aircraft mechanical engineer and been working my own around cars for 10 years i know a misfire when i hear one. Thats not meant to sound insulting or anything haha sorry.
Ill check the plugs see where that takes me.
I seen someone mention something on another post about camshaft sensor? would that effect anything?

thanks alot.

 

[turkie172]

Yea but with only 6 posts and asking what oil in the spark plugs holes will do you can see where I'm coming from at least we are trying to help. Part-time Mechanic 6+ IOM TT wins, many NW200 Wins, many Ulster Grandprix wins and current lap record, 600 British Supersport Championship winner and the other bike was second that year, British Superstock Champion and all part time since 2006 but with the rest of the team and the best riders of course that's only the bikes I was on that side of the garage for.


Not a good picture so you cant identify me and punch me in the mouth.

Let us all know how you get on and what you find it's great when a post ends with a solution.

 

[Liam Gunby]

yea i see where your coming from. Im no mechanic but i can do basics. My training is on Eurofighter Typhoons so military aviation.
i ask about oil around plugs as i thought it may be a detrimental fault i.e coming up past the plugs. but if its just from silly idiots spilling it i can deal with that.

I only ask these questions because people will have had more experience with clios than me, especially the phase 3's.

Thanks alot for you help anyway i will hopefully have a chance to look more in depth this weekend.

 

[turkie172]

Well you got a misfire not a fire missile. Just check the obvious easy stuff but it might come down to swapping stuff around there is a specialist near you even rs running Leeds get it mapped he knows all the Renault sports. Meet with someone on here and swap the easy stuff in a car park like plugs and coil packs


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[Pav]

oil in the plugs can be caused by oil leaking through the engine block bolts..lots of people have it on here..i cured my by taking them out 1 by one and resealing with some heat resistant silicon..easy enough
may be worth a try too if you have a leakage from the top of the block..

 

[Liam Gunby]

Update-

So last night i removed all the coils and all the plugs one by one. All plugs look brand new still...

Coils look alright..... :/ the spring inside of them is quite greasy (not sure if its meant to be)
The first one, ie as your looking at engine, the one nearest oil fill cap, was quite loose. Usually when you remove them they pull out with abit of suction n a lil pop. This one didnt :/ was no resistance to removing it.

Also when i pulled it up, it also brought up the item next to it that the 8mm bolt is also attached to.. (don't know what this is sits inside the head.......)

Getting it scanned tonight for potential fault codes.

Any thoughts?

thanks alot

 

[Pav]

im out really..hope it gets sorted...

 

[Liam Gunby]

im out really..hope it gets sorted...

thanks for your help

 

[Pav]

no worries..just feedback when you know a bit more..would love to know what it is that's annoying you

 

[Liam Gunby]

yea i will do pal hopefully will know more later today