Thanks for the replies, but I filled up last week. The common issues are: 1. It happens on a return trip from my business perhaps about 2 - 3 hours after previous use so the engine is not stone cold. 2. I'm travelling up a long hill, about 3/4 mile and I've probably been motoring for about 5 min from startup. However I came up the same hill the other way earlier in the day. 3. I loose serious engine power when the warning light comes on until the engine is stopped then restarted. The engine regains full power although the warning light remains on. It went off the first time after about 3 days. Grumble grumble - Phil