Wednesday, September 24th, 2008 AT 9:07 PM
1999 Cadillac Seville SLS 8cyl 4.6L 98,000 miles hard to start after sitting overnight or more than an hour and now it recently backfired. I change the oil every 3000 miles and changed the all the spark plugs & wires 8000 miles ago. What could be the problem?