i have an 03 GMC and just bought it about a month ago and notice that it takes awhile to start. I know about the glow plug warning light and what not. The problem is after driving for awhile or after it gets up to operationg temp it takes about 2-3 seconds to start at least. It turns over just fine. Its got 92k miles. Any help please! Dont wanna get raped from the dealer! Glow plugs? Spark Plugs? Maybe fuel issue like a fuel filter???