I have recently experienced a strange fault with my 1996 Vauxhall Astra MK3. Every now and then (about every 6-8 weeks) while driving, my engine light comes on and the whole car seems to suddenly slow down, and loses engine power. This lasts for about 3 seconds before the engine power suddenly kicks in again and returns to normal. It almost feels as though Iím dragging an anvil along the road for a few seconds!

This usually happens at a speed between 20 and 40mph, can occur while accelerating or while travelling at a steady speed, and usually happens after Iíve been driving for 10-20 mins. Thereís very little else consistent about it so I canít figure out what conditions might cause this fault to show itself!

(Last nightís occurrence happened after Iíd been driving for about 15 mins, and about 5 mins after Iíd been to the petrol station to top up. The slowdown happened while I was driving at a steady 40mph on a dual carriageway)

It doesnít really cause me any major problems as it occurs so infrequently, but Iím just worried it might be a symptom of something more serious, or expensive! Do any of you highly knowledgeable chaps have any ideas what the problem might be?

thanks! Jonathan