Scenic 1.6 - misfire

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Sun 24 Jun 2007 20:57
Scenic 1.6 - misfire - JustMike
Recently had to change one of the coils on my wifes 2002 1.6 Scenic as it was running on 3 - the coil was no good.3 months later Its started to misfire on a different cylinder (3) when I change the coil it then runs OK for a while but the coil I take out is wet and has rusty water marks on the bottom.

If I take out the spark plug will rubbish drop into the cylinder ? Is it likely to be a head gasket job - its only done 30K ? Dont treat me gently - just tell me what you think !! Please.

Is it a big job to change the head gasket.

Thanks ,
Mike

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Sun 24 Jun 2007 21:38
Scenic misfire - MerlinTec
Not head gasket just coils they go all the time.
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Mon 25 Jun 2007 11:02
Scenic 1.6 - misfire - Victorbox
"If I take out the spark plug will rubbish drop into the cylinder"

Not if you carefully clean around the plug base with an old paint brush or similar before you remove the plug.
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Mon 25 Jun 2007 12:15
Scenic 1.6 - misfire - yorkiebar
EXTREME CAUTION NEEDED!


If water is present around spark plug, when it is removed this will drain into the cylinder. If you then put in new plug and turn over the engine the chances are you will cause SEVERE DAMAGE!


Seek advice from a garage, to remove this water first and then work out where its coming from. If its coolant it could well be the start of head gasket failure!

If its not then where is it from etc and how can you stop it?
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Mon 25 Jun 2007 12:32
Scenic 1.6 - misfire - Screwloose
Mike

No need to panic. They all do that and are routinely full of water when the plugs are changed.

It's a silly design fault on 16-valve Scenics; all the water from the screen runs down the scuttle - and drips straight on to the coils, filling their deep wells.

There is an official fix from Renault. It's a strip of sticky-backed foam rubber for the scuttle that "cures" the problem - for about a month - and then gets all gungy and green and doesn't work anymore.

Plaster the coil rubbers with di-electric silicon grease when you replace them with Denso ones. [They don't fail like the Sagem ones.]
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Mon 25 Jun 2007 12:34
Scenic 1.6 - misfire - Aprilia
I don't think it will be the HG.

Blow out the area around the plug with compressed air.
Aren't you supposed to use a silicone sealer around these coils to stop water getting in? (check with dealer - I'm not sure, because I avoid Renaults, but IIRC a sealant IS required).
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Mon 25 Jun 2007 12:35
Scenic 1.6 - misfire - Aprilia
Ignore my post - just seen Screwloose's and I'm sure he's had a lot more experience with these!
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Mon 25 Jun 2007 23:43
Scenic 1.6 - misfire - JustMike
Thankyou Screwloose for your reassuring wisdom and Aprilia (who is invariably worth listening to )also needs a mention for bowing to your greater knowledge on this subject - that sort of honesty would benefit many of our politicians - but I dont expect to see it !

I'll invest happily in some suitable silicone grease and gungy tape now I dont have to worry about the head gasket.

Thanks to all.

Mike
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