I have a MK5 1.4 Astra 54 reg when I started it recently the electronics lamp stayed on ( car with spanner ) I let it run for a few minuets then switched off, when I switched on the ignition again the lamp came on but went off when I restarted the engine, but to be safe I had a diagnostics check done and its showing a fault with the camshaft speed sensor, I am waiting for a replacement sensor but have noticed the petrol consumption has doubled has anyone had this problem