i have an 85 deville. It has been acting up lately. it has almost 250k on it, and the dash has been disappearing lately. (just the gas gauge and heater display.) The heater display reads -151, and the gas gauge just disappears. I currently have the heater core bypassed, cuz it leaks and I don't have the money to fix it just yet. Could that be my problem. It does it mostly when the engine is at operating temp, but it also comes back on sometimes even when the engine is hot. Please help, cuz it is hard to keep track of how much gas I got when I only get a glimpse of it each morning.