I have a 1997 Chevy Silveradoo with a 5.7 litre engine. Recently it has started to miss badly when in idle. I had it scoped of which thecomputer stated that at first cylinders 5 and 7 were missing....less than a minute later 5 and 7 were firing again but cylinder 4 was now missing...then it was neither 5,7, or 4, but only 3 missing. I have recently changed all spark plugs and wires less than 60 000km with orignal OEM parts (AC Delco). Also, it is becoming harder to start with the first turn of the key. I suspect the fuel pump, but was wondering if anyone else has had similar symptoms before. Thanks for your input into the matter.