I was driving along in my '93 Volvo 850 when there was a sudden loss of power and the engine cut out and refused to start. The engine appears to turn over with the starter, though there is a high pitched whine from it. But even under tow I could not get the engine to fire up. I think the system relay is fine and I get a once-only spurt of petrol from the test valve (should there be a continuous spurting of fuel from it?). I have read most of the available tips on the site and have tried out all suggestions but I'm still grounded. I would appreciate help from anyone who has had similar experience or from anyone who knows the fix.