The Mégane II Owners' Club

I have a 2005, Renault Megane Estate, (1.9 DCi), a few weeks back the car would not start, although the engine turned-over. We had the RAC attend and they got it started by spraying a fluid around the injectors. I drove to a trusted, reliable garage who sent all four injectors for testing these have been returned without any identified defect, also the following has been checked or replaced;

Battery replaced;
Cam belt replaced and timing checked;
Electrics no issues found;
Fuel delivery ok;
Sparks and leads ok.

I'm sure there are other things which I don't recall, but the repair garage is at a loss, they are suggesting the head gasket but this is only a investigative step and will cost a considerable sum, more than what the car is worth.

The alternative is scrap, something I'm reluctant to do but also do not want to throw good money after bad. any thoughts suggestions appreciated.

Sparks and leads OK ???
You have a diesel it doesn't have spark plugs.

I am having an intermittent starting problem with my 1.5 diesel as well. Turns over but doesn't fire up.
I bought a bluetooth diagnotic OBDII fault reader and glowplug(open circuit) and Fuel pressure regulator were flagged up.
Replaced all 4 glowplugs(£17) although in retrospect I think the problem was just a loose connector on one of them and replaced the fuel pressure regulator(£35), should've tested the existing one but didn't.
I also replaced the fuel filter(£25) while I was there.
All seemed ok, but it is still unreliable on starting, maybe 8 times out of 10 it will and 2 times not.
I've read that the fuel pressure regulator fault can also point to issues with the fuel rail pressure sensor, although Haynes manual says on the 1.5 it shouldn't be removed.
I've asked on here if anyone knows why, but have yet to receive an answer.
I've bought a second hand one but will test the old one first.

Obvious suggestion is get hold of a diagnostic fault reader and see what it throws up.
They are very cheap now, infact the first time I used one I bought it on Amazon used it then returned it for a full refund, minus the postage.
You really need to know where the problem originates before throwing money at it.