2001 Cadillac Deville DTS Drove fine for the two months I've had it. Always started without delay, until today. Checked battery, fuses, and relay. All ok. Researched as much as I could and can't figure it out. Other issues that may be related: Heavy leak topside of the engine, I'm guessing valve gasket. Could this have affected starting? In dash temp cluster has never worked, possible it's disconnected to hide overheated engine? No leak in cooling system so I don't believe it's a blown engine and oil is only down a quart or so. Check engine light is always on, even when ignition engaged. Any ideas, I'm desperate.. Any time I've ever had issues with a starter I've always known before hand, this was just sudden. I do all my own work, but this car is backwards as it gets.