Clio MK2 1.6 16V
When facing downhill my car will not start, it try to start but stops the ignition sound after a second or so, the first time it happend I didn't have much fuel so I thought it might be that but the third time I had 3/4 tank and would not start I rolled it to a flat and still wouldn't start, eventually it did and I revved the engine to get some fuel in the engine then when I took my foot off the accelerator it died again like the idling wasn't working.....any ideas what's happening please