Weird one this, SWMBO has a Megane Scenic that has had recent starting issues, I neglect it to be fair, it never gets maintained, bangernomics at its best, In SWMBO's job she really needs to have a disposable car.

I thought i would treat it to a service, so plugs, leads, filters, oil that should about do it!

Checked the coolant and it was near empty :eek: never checked the coolant in 18 months but to give it its dues its never overheated.

I Flushed the coolant when we first got it as it looked a bit muddy, topped up with antifreeze/water and that was it.

Ran the car for half an hour or so around the town and as I got back to the drive I thought I would check if the coolant had settled and needed topping up, by that time it was darkish and I couldnt see the coolant levels, I couldnt find a torch in the garage so grabbed a lighter, put it over the top of the water bottle and WOOF, the vapours caught and shot out as it drew a vac :eek:

To check it wasnt a one off I had a go again tonight and sure enough, a little coolant used (less than a tea cup) and WOOF as the lighter went over it, lost all the hair off my hand

So my guess is its a leaking head gasket, some hydrocarbons in the water, so exhaust gasses getting through. any thoughts?

No emulsification, steam, smoke etc, just the occasional poor starting (Poor compression maybe) and the woofing :P

Yep, my guess would be headgasket too

If it's the old 1600 they were well known for head gasket failure. Renault replaced a few as a 'goodwill gesture' if the cars had a FSH and low miles.

It's either HGF, or you're using methanol anti-freeze?

What and di-ethanol antifreeze isn't flammable when hot?

The article on flammable coolant on t'internet ive been reading is more about the combustion of the liquid rather than the gasses and the flashpoint was at a high sustained temperature, but the small coolant loss, evident again when I checked again today hints at a hairline link between a water track and a cylinder. I'm just waiting for SWMBO to return from work and I'll give it a compression test.

And the coolant was empty so topped up with 'cooncil juice' in the meantime so no presence of any AF

Good thing is its a fairly easy HG swap and in true bangernomics style can be done for less than £100